AP

Former Alaska Gov. Sarah Palin (R) announced she will not run for president.

Sarah Palin is not running for president, a source confirms to NBC News.

Conservative radio talk-show host Mark Levin read her statement on his radio show.

*** UPDATE *** Here's Palin's letter, which was also read on the radio show:

October 5, 2011

Wasilla, Alaska

After much prayer and serious consideration, I have decided that I will not be seeking the 2012 GOP nomination for President of the United States. As always, my family comes first and obviously Todd and I put great consideration into family life before making this decision. When we serve, we devote ourselves to God, family and country. My decision maintains this order.

My decision is based upon a review of what common sense Conservatives and Independents have accomplished, especially over the last year. I believe that at this time I can be more effective in a decisive role to help elect other true public servants to office – from the nation’s governors to Congressional seats and the Presidency. We need to continue to actively and aggressively help those who will stop the “fundamental transformation” of our nation and instead seek the restoration of our greatness, our goodness and our constitutional republic based on the rule of law.

From the bottom of my heart I thank those who have supported me and defended my record throughout the years, and encouraged me to run for President. Know that by working together we can bring this country back – and as I’ve always said, one doesn’t need a title to help do it. 

I will continue driving the discussion for freedom and free markets, including in the race for President where our candidates must embrace immediate action toward energy independence through domestic resource developments of conventional energy sources, along with renewables. We must reduce tax burdens and onerous regulations that kill American industry, and our candidates must always push to minimize government to strengthen the economy and allow the private sector to create jobs. 

Those will be our priorities so Americans can be confident that a smaller, smarter government that is truly of the people, by the people, and for the people can better serve this most exceptional nation. 

In the coming weeks I will help coordinate strategies to assist in replacing the President, re-taking the Senate, and maintaining the House.

Thank you again for all your support. Let’s unite to restore this country! 

God bless America.

– Sarah Palin

Scott Olson / Getty Images

Former Alaska Gov. Sarah Palin speaks to supporters during the Tea Party of America's "Restoring America" event Saturday at the Indianola Balloon Festival Grounds in Indianola, Iowa.

By NBC's Alex Moe and Andrew Rafferty

INDIANOLA, Iowa - At a rain soaked field in the first-in-the-nation caucus state, Sarah Palin delivered a speech in front of a couple thousand supporters that railed not only against President Barack Obama but also criticized the Republican presidential field.

Palin told the crowd at the National Balloon Classic field that the permanent political class and "crony capitalism" of both parties is what has caused this nation's fiscal problems. But she specifically questioned the Republican field of candidates -- asking if their campaign contributions leave them beholden to special interests.

"To be fair some GOP candidates, they also raise mammoth amounts of cash and we need to ask them too, ‘What if anything do their donors expect in return for their investments?’" Palin said during the Tea Party of America's "Restoring America" event. "We need to know this because our country can’t afford more trillion-dollar thank-you notes to campaign backers."

After the speech, Palin told NBC News the goal of Saturday's speech was "to lay out a plan that can help restore what is good and right and free about America and to start tackling the crony capitalism that really is ... the foundation of our problems."

On this day three years ago, Palin spoke as the vice presidential nominee to a packed convention center in St. Paul, Minn., at the Republican Convention. Today, she spoke to an enthusiastic Tea Party crowd in a speech that was sporadically interrupted by chants of "Run, Sarah, run."

But unlike three years ago, she pushed back against the Republican establishment, promoting the ideals of the Tea Party movement.

At one point, the former Alaskan governor even made a joke about the emphasis put on national polls:

"Polls," Palin said, "they're for strippers and cross-country skiers."

One big question remained on the minds of those who sat through periods of torrential downpours in the Hawkeye State following the almost 40-minute speech -- Will she herself be a contender in the 2012 race?

"I've admired her ever since she came on the scene," attendee Miki Booth of Wyandotte, Okla., said. "This country is in bad shape and I'd really like to see us go back to the principles of the founding fathers and I think Sarah Palin can lead us back to those ideals."

Palin now heads to New Hampshire for a Tea Party Express rally on Labor Day continuing to fuel speculation that she will soon become a presidential candidate.

URBANDALE, Iowa -- Hundreds of supporters greeted Sarah Palin as she made a somewhat unannounced visit to a Conservatices4Palin meeting here last night at a local restaurant.

On the eve of her much-anticipated appearance at a Tea Party rally in Indianola, Palin barely made her way through the packed room in The Machine Shed restaurant. On-going chants of “Run, Sarah, run” broke out as she shook hands, took pictures, and signed autographs with those in attendance. To the disappointment of some, she did not give any formal remarks or get all the way around the meeting space. And she also took no questions from the media.

If last night’s “surprise” visit is any indication of today's event, it is going to be large. An entire bus from Texas dropped off a few dozen people with a big “Texas is Palin country” sign on the side of the bus. Supporters were also there from California, Illinois, and so forth.

Palin and her aides have not said if the former Alaska governor will give any indication on her presidential plans. Palin also has a trip scheduled to that other early nominating state -- New Hampshire -- Monday, which is Labor Day.

DES MOINES, IA –- This Labor Day weekend, Sarah Palin is returning to two key presidential primary states -- here to Iowa on Saturday and to New Hampshire on Monday.

And the question remains the same: Is she running for president, or not?

Indeed, there's been plenty of speculation that the former Alaskan governor might jump into the 2012 race with her speech in the Hawkeye State, but much of those rumors have been put to rest. Instead, Palin will attempt to “deliver a sharp indictment of President Barack Obama” and “contrast herself against the current crop of GOP candidates” in her speech in Indianola, CNN reported.

Last week Palin posted links to two videos on Facebook teasing her speech in Iowa, and both videos were about President Obama. "America is waiting for the president to make good on this promise," Palin wrote referring to a video where Obama said he would cut the deficit in half.

Palin is scheduled to speak shortly after 2:15 p.m. ET, Tea Party of America President Ken Crow told NBC News. Crow does not have a crowd estimate, because admission to the "Restoring America" rally is free. But many are expecting thousands to be in attendance. One person from Florida who contacted Crow said that she sold her car to be able to afford to come to hear Palin speak in Iowa.
 
“There is already a crowd in the parking lot camping out,” Crow said Friday, “We will take care of however many come.” 
 
The event also happens to coincide with the three-year anniversary of Gov. Palin’s address to the Republican National Convention in 2008, when she was the GOP vice-presidential nominee.
 
Palin visited Iowa a few weeks ago as part of her “One Nation” bus tour –- attending the Iowa State Fair.

And this return trip has already produced a fair share of drama, which isn't foreign to Palin-related events. Organizers decided to add Christine O’Donnell to the program earlier this week. O’Donnell -- who ran unsuccessfully for a Delaware Senate seat during the 2010 cycle and was endorsed by Palin -- was invited to speak Saturday, then un-invited, then re-invited, and finally her invitation was withdrawn indefinitely Wednesday morning.
 
"I had to cancel Ms. O'Donnell" after a conversation with Palin aides, Crow told NBC News.
 
Sometime after Saturday’s rally, Palin will head to the first-in-the-nation primary state of New Hampshire. She is speaking at a Tea Party Express event in Manchester on Labor Day, shortly before numerous GOP presidential candidates speak at a forum in South Carolina.

Palin has made reference to the end of September being the “drop dead” date of deciding whether she will enter the race.

DES MOINES -- Tea Party of America President Ken Crow told NBC News, "I had to cancel Ms. O'Donnell" after a conversation with Sarah Palin aides -- and is now hopeful Palin will attend the Saturday rally in Indianola.

He was told by Palin's team that he'd have a final answer shortly.

This comes after failed Delaware Senate candidate Christine O'Donnell was in, then out, then back in, and now indefinitely out. And Palin was in, then "on hold."

The group has spent about $100,000 on the event for Palin and are thus waiting "with baited breath" for an answer. An official press release will come out after Palin people give Crow final word.

NBC News has not received comment from Palin's team so far.

This Palin video is too well produced for someone who doesn’t want people to think she’s at least thinking about running for president.

This thank you to Iowa video is complete with cheery music and laudatory press statements, including what could be seen as a subtle shot at Michele Bachmann on security. She includes Don Lemon from CNN, who got into a tussle with Bachmann’s security team, lauding the access he had to Palin’s team and that she answered all of his questions.

And, of course, it’s hard to ignore that growling bear at the end as she promotes a Sept. 3rd rally in Iowa.

Alex Moe/NBC News

Gov. Sarah Palin inspects Ronald Reagan memorabilia at the Ronald Reagan museum at Eureka College in Eureka, Ill.

After a roughly two-month hiatus, Sarah Palin's "One Nation" bus tour was back on the road this weekend. This time, she traveled across the Midwest, where she learned about past U.S. presidents -- and reacted to developing news about the 2012 presidential race.
 
Earlier this week, the former Alaska governor announced on her website that she would be stopping by the Iowa State Fair on Friday, which put the political world on edge as she was coming to such an important early nominating state -- the day before the closely watched Ames Straw Poll.
 
While at the fair, Palin said that she still considers herself a “potential candidate,” and that she will make her decision in the coming months, so her supporters will have time to choose another candidate if she’s a no.
 
“I don't want to be seen as stringing people along,” Palin said at the state fair when speaking of a timeline to decide if she will run for president this cycle.
 
But after leaving Iowa early Saturday, the bus trip took a different focus -- on American history. Like the tour through the Northeast back in May, Palin (along with her husband Todd, daughter Piper, and her niece) visited some significant historical sites.
 
"This is one of those places everyone in America should come to get a sense of Ronald Reagan's foundation -- to understand his humbleness and graciousness,” the 2008 vice presidential candidate said in Dixon, IL outside the boyhood home of the 40th president.
 
As the SarahPAC caravan (consisting of an SUV, minivan, and bus) drove through Illinois -- even on some dirt roads -- passing cars would slow down to snap pictures out the window, and some even honked and waved. Palin was greeted at every stop, including some of the hotels, by crowds of people wishing to take a photo with her or snag an autograph.
 
While the family was visiting Eureka College, Reagan's alma mater in Illinois, the results of the Ames Straw Poll were released –- a sobering reminder that the presidential campaign is fully underway without her.
 
Michele Bachmann's win, Palin told NBC News, will not impact her decision whether or not she jumps in the race. “The prediction was that it would either be Ron Paul or Michele Bachmann, because they spent a lot of time and energy to make sure they had delegates there who would cast those votes -- so not really a surprise,” Palin said in Eureka.
 
And just a few hours after the straw poll, as the Palin family was preparing to make their last stop on this leg of the tour to the Abraham Lincoln Presidential Museum in Springfield, IL, news broke that former Gov. Tim Pawlenty was dropping out of the race.
 
“So I really, really hope the best for Gov. Pawlenty," Palin told NBC News during her tour of the museum. "He is a good man, and disappointed that he dropped out.”
 
“We still have many months to go, and I think we will see more people coming and going,” Palin added during a follow-up question standing in front of a replica White House.
 
Palin is scheduled to come back to the Hawkeye State Labor Day weekend.

EUREKA, Ill. -- Sarah Palin told NBC News that Rep. Michele Bachmann winning the straw poll will not affect her decision to run or not, calling her win "not much of a surprise."

"It is not much of a surprise," Palin told NBC News. "I think, at this point, it is more of a test of organization. ... The prediction was that it would either be Ron Paul or Michele Bachmann, because they spent a lot of time and energy to make sure they had delegates there who would cast those votes, so not really a surprise. It's a part of the process, another step, again, a test about organization at this point and many more contests up ahead."

DIXON, Ill. -- Sarah Palin continued her "One Nation" bus tour today here, the boyhood hometown of former President Ronald Reagan. The former governor, along with her husband, daughter Piper, and niece were shown around Reagan's home; Rock River, where he was a lifeguard; and passed a statue in his honor. Ann Lewis, chairwoman of the Dixon Reagan Sentinel Commission escorted the Palin family around.

Palin told NBC News that it was important for her to come here, because "this is one of those places everyone in America should come to get a sense of Ronald Reagan's foundation -- to understand his humbleness and graciousness."
 
At all two stops, she was greeted by numerous supporters asking for autographs and pictures. Palin also made one reference to her new granddaughter that was born a few days ago when speaking with supporter at the Reagan house.

A lot of the cars passing the bus take photos as they drive past. Some wave and a couple have then followed the bus until it stops to meet Palin.

Leaving Dixon now. Next location is unknown.

Michele Bachmann made what appears to be another gaffe on history. When asked by ABC this morning to explain why she once said that the nation's Founding Fathers fought tirelessly to end slavery, Bachmann replied:

Well if you look at one of our Founding Fathers, John Quincy Adams, that’s absolutely true. He was a very young boy when he was with his father serving essentially as his father’s secretary. He tirelessly worked throughout his life to make sure that we did in fact one day eradicate slavery….

The problem: John Quincy Adams was just 8 years old when the Declaration of Independence was signed.

But instead of accusing ABC of asking a "gotcha" question -- or complaining of media bias -- Bachmann simply moved on to the next question. And that's what she also did after FOX News host Chris Wallace asked if she was a "flake" on Sunday.

"He did apologize, and I was happy to accept his apology," Bachmann told FOX's Hannity last night. "And we'll move on."

That's a clear contrast with Sarah Palin, who rarely moves on.

While we've complained about the constant comparisons between Bachmann and Palin -- though both are conservative women, they have different records and political identities -- Palin has been much more willing to engage her critics and the news media.

After all, Palin directly challenged David Letterman after the late-night comedian joked about one of her daughters; she was involved in a public spat with the father of her grandson; and she routinely pushes back against the media, like this Tweet from yesterday:

sigh* media making things up again MT @POLITICO2012: Sarah Palin reaching out to IOWA operatives http://politi.co/j9kQko by@maghabepolitico

When NBC's Matt Lauer asked Bachmann on "TODAY" this morning if she feared being "Palin-ized" -- i.e., attacked the same way Palin was -- Bachmann replied this way:

“That’s something that goes with the territory… There will be attacks to come.”

Former Alaska Gov. Sarah Palin (R) is headed back into the political spotlight. The only question is for how long.

Palin, who may or may not run for president, will attend on Tuesday the premiere of a glowing pro-Palin documentary in Iowa, which holds the first presidential nominating contest.

The documentary, “The Undefeated,” chronicles her accomplishments as Alaska governor, highlights the attacks she received from Hollywood and the media when she was the GOP’s vice-presidential nominee in 2008 and throws some punches at the Republican Party’s establishment, accusing GOP leaders of not defending her.

Although Palin played no personal role in producing the documentary, she has screened the film (and so have numerous members of the political press corps).

Palin’s appearance in Iowa could potentially step on Michele Bachmann’s official presidential announcement in the Hawkeye State, which takes place on Monday.

Palin was accused of stepping on Mitt Romney’s official presidential announcement in New Hampshire earlier this month, when her East Coast bus tour arrived in the Granite State the same day as Romney’s announcement.