Elizabeth Warren's plum speaking slot at next month's Democratic National Convention has prompted misgivings among some centrist Democrats, who worry the Massachusetts Senate candidate could turn off independent voters.

Democrats announced this week that they had tapped Warren, the former consumer financial protection czar who's challenging Sen. Scott Brown (R-MA) this fall, to deliver a prime time address before a national television audience. A popular figure among progressive activists, Warren has built a reputation as an outspoken critic of the excesses of Wall Street — a kind of populism Democrats are hoping to showcase at their convention.

But some members of the party wonder if selecting a figure like Warren — whom Republicans have sought to characterize as an out-of-touch elitist and cloistered Harvard professor — might hurt the party on a national level. She will speak the evening of Weds., Sept. 5, before a famed centrist Democrat: former President Bill Clinton.

“Having someone from the more extreme wing of the party, being given the primetime slot sends the wrong message to people in the middle who are legitimately up for grabs in this race," said Pennsylvania Rep. Jason Altmire (D-PA).

Altmire is among the dwindling ranks of the Blue Dog Coalition, the group of moderate Democrats in the House. These lawmakers typically hail from rural or working class districts and favor more fiscally responsible policies and permissive gun rights.

They've seen their representation in Congress shrink, though. The caucus had 54 members before the 2010 midterm elections, which shrunk to 25 this Congress. At least seven of them — including Altmire, who lost a primary to a more liberal Democratic Rep. Mark Critz (PA) — won't be returning to Washington next year.

Altmire said that while Warren's progressivism might play well in Massachusetts, the party might be better-served by a different prime time speaker.

"If you’re trying to win over people from the center — moderates and centrists who could go either way — I would guess there are other faces you could put forward who would be better for that," he said.

Another retiring Blue Dog, Oklahoma Rep. Dan Boren, argued for better geographic representation in the convention's prime speaking slots.

“If we are going to become a big tent, we need language that speaks to fiscal responsibility, we need some speakers who are from the South, we are already winning in the coastal areas of the country,” Boren told NBC News. “if you’re going to speak to the 4 percent [of undecided swing state voters] you’re going to want somebody who can appeal to independents, I think it would be better to have somebody from more Middle America.”

But other Democratic moderates expressed a greater comfort level with Warren relative to some of their colleagues.

Virginia Rep. Gerry Connolly (D), who won re-election by only 981 votes last cycle, called Warren a "very engaging speaker" who has a "real ability to speak to the lay person about what the underlining dynamics are in the economy."

That's precisely what Democrats are hoping to project with Warren's speech. From a working class background in Oklahoma, Warren speaks often about themes of opportunity and strengthening the middle class. To that end, Connolly said he thought Warren would “highlight advocacy for the middle class.”

Ohio Rep. Tim Ryan (D) saw particular opportunity for Warren to appeal to women: "She will definitely speak to working class women, and I don’t think she’s going to turn anybody off. She comes across as pretty tough; I don’t see her coming off as a heady intellectual, it’s inner toughness about taking on the banks.”

Prime time speakers at party conventions are usually selected to help broaden the party's appeal to voters who don't adhere to strict political orthodoxies. The choice of San Antonio Mayor Julián Castro to keynote the Democratic convention is a good example of that.

One Democratic operative NBC News that Warren could do that, too, but, “she carries a risk."

"I’d say she’s high risk, high reward," said the operative. "People could relate to her down with the 'greedy guys' talk, or see her as polarizing and part of the problem.”

But another retiring Blue Dog, North Carolina Rep. Health Shuler, expressed concern that Democrats could risk seeming as though they're uninterested in moderates by putting Warren front-and-center.

“I hope in time, Democrats realize in order for us to appeal to more voters, we need to highlight more moderates, not show just the far left of the party but in fact give people an opportunity to see we are a big tent," he said, pointing to the GOP's struggles with the Tea Party as a cautionary tale. "That helps us with independents; we don’t want to be pushing out moderates just like the Republicans are doing.”

It’s a spot that launched, for example, Barack Obama in 2004 when he was just a fresh-faced 42-year-old state senator from Illinois.

So can he live up to the expectations?

Castro, 37 -- a Harvard Law and Stanford grad, who will be the first Hispanic to deliver the address -- is largely unknown to a national audience. But looking at past speeches and videos, his personality, humor, and ability to deliver a stirring speech that draws on his compelling personal story are clear.

The Obama campaign has watched Castro closely, made him a campaign co-chairman, and says he has been effective on the campaign trail for the president.

One recent speech that might give some clues as to points he might touch on, as well as his cadence, delivery, and style, was his keynote address at the Texas Democratic Convention just last month.

And then there was his public spat with Charles Barkley, the former NBA basketball player who criticized San Antonio, particularly its women. Castro fired back in a YouTube video that went viral and even won over Barkley.

'Somebody who won't screw up'

Castro’s keynote speech in Texas last month reflected the seriousness and potential of someone who has won plaudits like this:

“People look at him and say, ‘Finally, we have somebody who won’t screw up,’” John A. Garcia, a political science professor at the University of Arizona, told the New York Times magazine in 2010. Of course, he’s still young, and he might be too good to be true, but if I were betting on the next national Hispanic political leader, I’d bet on Julián.”

Of course, in the current political climate in Texas, it is difficult for a Democrat to break through, at least for now. Even though the majority of voters are minorities in the Lone Star State, none of its statewide officeholders are Democrats.

Belief in government

There was plenty in Castro’s Texas convention keynote about the American Dream, but rather than making his story solely about his own drive, determination, and individual responsibility, he laid out what government needs to do to help pave the way of fairness, including on education, infrastructure, and new technology.

Castro supports affirmative action, he has said, because it gave him and his identical twin brother, Joaquín, the opportunity to go to elite colleges. Joaquín -- who, like his brother, also went to Stanford and Harvard -- is a state representative favored to win the open 20^thcongressional district seat to replace retiring longtime Rep. Charlie Gonzalez (D).

“Joaquín and I got into Stanford because of affirmative action,” Castro told the New York Times. “I scored 1,210 on my SATs, which was lower than the median matriculating student. But I did fine in college and in law school. So did Joaquín. I’m a strong supporter of affirmative action, because I’ve seen it work in my own life.”

What he might say

Castro strives for the similar unity rhetoric that made Obama famous. Here he was in that speech before Texas Democrats:

“In San Antonio, collaboration is our currency. … These days we hear a lot of talk about how Americans are tired of politics. They’re disillusioned with government, but I think the real issue is that Americans are tired of politicians battling over manufactured issues instead of solving real ones.”

But he also lays blame at the feet of Republicans:

“Today’s Republican Party is leaving just about everyone behind. To them, compromise is a non-starter. Moderate is a four-letter word. You see folks are reevaluating their past political allegiances because people are fed up with the politics of division. They’re fed up with the politics of exclusion. They’re fed up with petty politics. And they’re fed up with Perry politics.”

And he tries to undercut what they stand for:

“Republicans haven’t just departed from the mainstream, they’ve departed from mainstream values. Since when does cutting health care for children make you the party of family values? Since when does denying women their basic rights make you the party of freedom and liberty? Since when does smoke-and-mirrors budgeting make you the party of fiscal accountability?”

He also gives Democrats want they want to hear -- about education, abortion, and immigration.

“We believe the real emergency is getting more students across the graduation stage not frivolous voter ID laws. We believe that veterans who risk their lives for us shouldn’t have to come home and fight for their own livelihoods here. We believe that woman’s right to privacy is a right to privacy is an individual liberty not a political wedge issue. We believe that it’s more important to build bridges to send Texas products across the world than to build a wall that cuts us off from it.”

He pivots from state politics to lay out the choice in the presidential election:

“This year’s presidential election will provide a very clear choice. President Obama inherited the worst economic crisis since the Great Depression. He acted to keep thousands of Texas teachers in the classroom and cops on the beat and made investments in the industries for the future. The president made a bold call to save our auto industry. And today, they’re back at work, making the best cars in the world.”

He seems to have the talking points down. During the speech, he touted private-sector job growth under Obama, including manufacturing jobs because of the auto bailout. He hit presumptive Republican nominee Mitt Romney for “Let Detroit go bankrupt” and Massachusetts being “47^th in job creation.”

He defended Obama’s health law, ending the war in Iraq, and killing Osama bin Laden. Sounding a lot like First Lady Michelle Obamabefore the president’s kickoff speech at Ohio State, he also called on the Democratic activists to do the grassroots work:

“We must reelect President Obama. In your neighborhoods, in your cities, in your counties, in your communities, get out there. Knock on doors. Call your friends. Text them. Tweet them. Email them. Heck, maybe even speak to them face to face. Do everything that you gotta do to get President Obama reelected in November.”

Toward the conclusion of his speech, he reached for the kind of rhetoric that can translate on a national stage.

A compelling personal story:

“I told you about my mother. Now I want to tell you about my grandmother, Victoria. By the time she was 6-years old, my grandmother was an orphan. She had to leave her home in Mexico to come to San Antonio with relatives who had agreed to take her in. My grandmother never made it past the third grade. She had to drop out of school to start working and help support her family. By the time, I was born, this incredible woman had taught herself to read and write in Spanish and English. She spent her whole life working because of her lack of education as a maid, a cook, and a babysitter – barely scraping by but still working hard to give my mother a good chance in life, so that my mother could give me an my brother an even better shot.

“My grandmother was a fantastic cook. By the way, a skill that never really transferred to Joaquín or me. And the day before Joaquín and I were born, she won $300 in a Menudo cook off. And that money came in pretty handy. In fact, she used it to help pay a hospital bill. My grandmother didn’t live to see us enter public service. But she probably would have found it extraordinary that just two generations after she got to San Antonio one grandson would be the mayor and the other would be on his way to the United States Congress.” 

Reverence for America:

“My family story is not special. What’s special is the America that’s made our possible. This is a nation like no other with unlimited potential. And a Texas where great journeys can be made in just the space of a generation.

Outlining the choice ahead:

“Today, Erica and I are the parents of a precious little girl. Carina Victoria. Now, I love my job. But I love even getting home at the end of the day and seeing her big smile and getting an even bigger hug. All of the time, I ask the questions that all of us parents wonder about – what will her life hold? What will her Texas look like? What America will she inherit? Will it shine with opportunity and possibility? Or be damaged and decayed? Will our Texas be left behind or will we shepherd America to its greatest days yet? We cannot leave the answers to chance! It shouldn’t be a coin toss!"

And a call to action (one could insert “America” for “Texas” in many spots, “Ohio” for “Panhandle,” “Florida” for “Rio Grande Valley”):

“So tonight, the future of Texas is calling on us -- from the Panhandle to the Rio Grande Valley. The need for common-sense values has never been more urgent. The future is calling us. Across the country, as he campaigns for reelection, President Obama is asking folks a very simple question: ‘Are you in?’ In fighting for our party’s future, for our state’s future, Texas Democrats, I ask you the same thing. Houston, are you in? Dallas, are you in? The valley, are you in? El Paso, are you in? San Antonio, are you in? Tonight, let us stand up as one party, one state, one Texas, and proudly say, We. Are. In! The future of Texas is calling on us. And we’re answering that call. Vamanos!”

GOP to also feature Latinos

Republicans at their convention a week earlier will also prominently highlight Latinos. They have plenty of elected Republican Hispanics to choose from, including Sen. Marco Rubio (R-FL); Ted Cruz (R-TX), who’s the heavy favorite to become Texas’ next senator after his win last night in the Texas GOP primary; popular New Mexico Gov. Susana Martinez; Nevada Gov. Brian Sandoval; and current Rep. Raul Labrador (R-ID).

Rubio’s and Cruz’s roots are from Cuba; Martinez and Sandoval trace theirs to Mexico; and Labrador’s family is from Puerto Rico.

According to the U.S. Census, Mexicans are the largest Hispanic group and the largest-growing group:

“About three-quarters of Hispanics in the United States reported as Mexican, Puerto Rican or Cuban origin in the 2010 Census. Mexican origin was the largest group, representing 63 percent of the total U.S. Hispanic population — up from 58 percent in 2000. This group increased by 54 percent and saw the largest numeric change (11.2 million), growing from 20.6 million in 2000 to 31.8 million in 2010. Mexicans accounted for about three-fourths of the 15.2 million increase in the total Hispanic population between 2000 and 2010. The Mexican origin population represented the largest Hispanic group in 40 states, with more than half of these states in the South and West regions of the country, along with two states in the Northeast and all 12 states in the Midwest.”

“Hispanics are going to play a very prominent role in both conventions,” a GOP strategist told First Read. “The Republican Party has now run a lot prominent elected Hispanics. … . In Texas, it elected a U.S. senator, and he’s conservative, and he’s Hispanic.”

The strategist, referring to Cruz, said Cruz may be Cuban, but he “is going to represent a whole heck of a lot of Mexican Americans.”

The strategist added, “I don’t foresee any problem with our ability to be able to communicate to this audience broadly and in a more narrow fashion. And we can do it with more authority than we’ve ever done it as a party.”

The strategist noted that it’s no longer top-down white party officials telling Hispanics they should join the GOP: it’s “Latinos who have done it and are doing it. We’re in a very strong position. There’s a reason Democrats put this guy up -- it’s because they know that.”

The Obama campaign, however, believes that Castro represents the differing economic visions between the parties.

“Mayor Castro is a rising leader in the party who has worked tirelessly to build San Antonio’s economy from the middle class out, by making investments in things like clean energy and innovative education programs that will lead to the creation of good-paying, sustainable jobs you can raise a family on,” Obama campaign spokesman Ben LaBolt said. “Having both the First Lady and Mayor Castro speak on the opening night of our convention will bring together two incredible leaders whose life stories both embody the promise of America -- that if you work hard and play by the rules, you can thrive.”

Defending the women of San Antonio from Charles Barkley

Charles Barkley outraged San Antonians two years ago when, on television, he criticized the city, especially its women.

“As much as I love San Antonio -- a great city, I’m not gonna miss it,” Barkley said. “One thing about San Antonio, them women down there, they got— My ass, my ass would look normal down there. I wanna tell you somethin’ -- they ain’t got no skinny women down there.”

The comment during TNT’s broadcast left analysts in the studio slack jawed. But Barkley reiterated it again this past May during the NBA playoffs: "Everyone knows San Antonio is a great city... They do have some big ol' women down here."

Castro had had enough. But rather than a huffy call for Barkley to apologize, Castro took to the camera and YouTube for a “Hey Chuck!”smack down that went viral. Castro ragged on Barkley’s fitness, lack of championship rings, and a horrifically awkward golf swing.

“You’ve not always been very kind in describing the women of San Antonio,” Castro says in the video. “Come to think of it, maybe that’s because we have a very different idea of what a beautiful woman looks like,” Castro deadpans when up pops a photo of Barkley dressed in drag.

Castro saved his best line for after playing video of Barkley’s golf swing: “Actually, that has nothing do with San Antonio. We just thought it was funny.”

The two later met, at the Alamo no less, and he had won Barkley over.

“I never met a mayor with a sense of humor before,” Barkley told Castro. “I want to thank you for taking the time for making that video. It was funny.”

He even changed his tune on other matters: “I like the women,” Barkley said, and he picked the Spurs to win in the playoffs.

In showcasing someone like Castro, Democrats hope to energize the base and also signal to the majority of Hispanics which party is looking out for them. One thing is clear -- both parties are well aware of Latino growth and know they need to make sure Hispanics are featured prominently.

As first reported by the New York Times, former president Bill Clinton will have a prominent role for the 2012 Democratic National Convention, speaking in primetime on Wednesday, Sept. 5, NBC’s Carrie Dann reports. The decision means that Vice President Biden will instead speak before the president on the final Thursday evening of the convention. The popular former president is expected to argue for Obama's economic policies in his speech.  "There's no one better to cut through on economic issues and lay out the choice in the election because he understands the consequences of the policy differences" from his own presidency, an aide said.

Sources say the decision to bump Biden to the final night of the convention was made jointly by the VP and the president. "He’ll build toward the President’s speech by giving unique insights and perspective of the President’s governing character and the challenges/decisions over the last four years in a way that only he can," says the aide of Biden's role.

The AP: “The move gives the Obama campaign an opportunity to take advantage of the former president's immense popularity and remind voters that a Democrat was in the White House the last time the American economy was thriving.”

And there’s this implicit comparison to the GOP: “Obama personally asked Clinton to speak at the convention and place Obama's name in nomination, and Clinton enthusiastically accepted, officials said. Clinton speaks regularly to Obama and to campaign officials about strategy. Clinton's prominent role at the convention will also allow Democrats to embrace party unity in a way that is impossible for Republican rival Mitt Romney. George W. Bush, the last Republican to hold the White House, remains politically toxic in some circles. While Bush has endorsed Romney, he is not involved in his campaign and has said he does not plan to attend the GOP convention.”

USA Today: “The prominent role for Clinton reflects the latest truce between the two presidents, who first clashed during the 2008 Democratic primaries when Obama defeated Hillary Rodham Clinton. More recently, the Obama team has been frustrated by Clinton comments complimenting Romney's business career and endorsing a different strategy on tax cuts.”

“In an appearance before the American Federation of Teachers conference in Detroit on Sunday, Vice President Joe Biden told attendees to look at Republicans' spending plans to see how much Republicans value education,” the Detroit Free Press writes.