From NBC's Kelly O'Donnell and Ken Strickland
Sen. Robert Byrd was taken to the hospital this morning after he "apparently stood up too fast this morning in his home and fell down," senior Byrd aides tell NBC.

"To err on the side of caution, his caregiver called an ambulance. He was taken to the hospital where he is currently being checked out. At this point in time there is no indication that he will be admitted."

Byrd, the West Virginia Democrat, is the longest-serving senator in U.S. history. In his ninth term, he was elected to the Senate in 1958. He is 91.

From NBC's Carrie Dann
In an interview with NBC's Kelly O'Donnell today, McCain took a step back from blaming Obama for infusing politics into the bailout negotiations, and he previewed fellow "underdog" Palin's debate appearance later this week.

Asked if he still believes that Obama and his Democratic colleagues fueled a partisan atmosphere on the Hill as lawmakers struggled over the economic recovery bill, McCain responded that he wants to "put that aside now."

"I believe that politics has played too great a role in this. I think that Speaker Pelosi's speech was very unnecessary and inflammatory," he said, "But that's not a reason for us not to work together and come up with a solution. I think it's time now not to fix the blame but to fix the problem."

In light of much national anticipation of Thursday's vice presidential debate, as well as the recent rash of bad reviews for Palin's performance in media interviews, McCain defended his running mate's governing style and "tradition."

"The American people have taken to her in a way that I have never seen before,"  he said. "Their appreciation for her is not because she has got a Ph.D. from Harvard. She doesn't. Their appreciation for her is her world view, her tradition, her adherence to good government."

McCain described Palin's handicap in her upcoming debate against Senate colleague Biden as comparable to his own challenges in facing Obama.

"I think she'll be fine," she said. "I also think that she's just like me in my debates. Got my work cut out for me. I am debating one of the most articulate people ever to come on the American scene."

From NBC's Kelly O'Donnell
Huckabee will drop out now, according to sources.

From NBC's Ron Allen and Kelly O'Donnell
A police motorcycle officer died after a crash escorting Clinton's motorcade in Dallas today. In a statement afterwards, Clinton called the accident is "devastating" news -- she feels "heart-sick" and expressed her condolences to the family and to the Dallas police department. Clinton placed a call to the chief, and she added that this reminds us of what people in law enforcement do everyday. "We respect their service."

VIDEO: A Dallas police officer was killed in a motor accident while escorting Sen. Hillary Clinton to a campaign rally. NBC's Peter Alexander reports.

Clinton looked profoundly upset by what had happened -- a routine police operation she's probably been part of countless times as first lady, senator and now presidential candidate.

It's also worth noting that at least two officers have died in accidents while working in motorcades for President Bush in the last few years. The incidents occurred in Honolulu and Albuquerque.

As of this writing, the Clinton motorcade is rolling slowly down a highway. We're heading to another event. It's such a contrast to the way motorcades usually race through cities and towns....with crowds catching a glimpse of dignitaries. The press bus is silent. I think everyone is just stunned. Such an unexpected tragedy.

*** UPDATE *** Per NBC's Christina Jamison, what was supposed to be a rally in Fort Worth is now being cut short. Senator Clinton will make brief remarks here in Fort Worth -- she spoke with the Dallas police chief on the drive over here, and then she is going to go visit the officer's family while the traveling press is taken to the airport.

From NBC's Kelly O'Donnell
A change in plans for a Huckabee fundraiser in Dallas today: The site had to be moved twice to accommodate a larger-than-expected attendance. Advisors say there just wasn't enough room, so the planned gathering went from a private home, to hotel space and then to a bigger meeting room in that hotel.

Sources say the goal for the fundraiser had been $50,000 to $75,000, but those expectations were upped to $150,000, but sources now say the campaign beat that and the number is closer to $250,000. Sources tell NBC News the Huckabee campaign has spent about $750,000 total.

Now hiring: Senior campaign officials say they are "adding staff almost daily." From a lean team of 45 paid staffers nationwide, Huckabee is adding employees in Iowa, New Hampshire and South Carolina. For example, the Iowa organization has been running with 14 paid workers plus as many as 15 to 20 full-time volunteers and more offering help hours at a time. The Iowa organization is expected to grow from 14 to 19 paid staffers this week. The six-person New Hampshire staff and five or six working South Carolina could see extra help with days as well.

Pardon our dust: Higher poll numbers appear to equate to more square footage. Huckabee's one and only office, a downtown Des Moines storefront has doubled in size. In Little Rock, sources say walls were "busted out" and overnight, the space tripled in size.

From NBC's Kelly O'Donnell
NBC News has learned that Jeri Thompson, wife of republican presidential candidate Fred Thompson, is canceling the first public event where she was to appear on her own. Jeri Thompson had previously agreed to participate in a high-profile forum featuring spouses of presidential hopefuls from both political parties. The event, Tuesday Oct 23rd in Long Beach, Calif., will be moderated by California First Lady Maria Shriver to discuss the balance of politics and family as part of her annual Women's Conference.  

Sources close to the 41-year-old mother of two small children say, "We regret that we cannot be there" and stressed, "We were apologetic." The reason cited for the cancellation is "scheduling." Jeri Thompson is scheduled to make her first solo trip campaigning as a surrogate for her husband next week.  She is also set to deliver a speech at the Jewish Coalition forum tomorrow with no press coverage.

Organizers of the Shriver event say they "heard rumblings yesterday" about a possible cancellation and expressed hope that "it's salvageable."  Planners called it a "brain scratcher" and noted that media kits and materials for the event already printed have Jeri Thompson listed as a participant.

Per NBC's Kelly O'Donnell, President Bush will discuss the departure of Agriculture Secretary Mike Johanns at 9:30 am ET. Johanns, the former governor of Nebraska, is leaving to run for the Senate seat being vacated by retiring Sen. Chuck Hagel (R). "Mr. Johanns would be the fourth Republican candidate in the field. While Nebraska is heavily Republican, the Senate vacancy is creating a potential opportunity for Democrats, who are trying to recruit Bob Kerrey, a former senator from Nebraska who is president of New School University in New York City, to run."

Also, O'Donnell reports that Bush will hold a press conference today in the the Brady Press Briefing Room at 10:45 am ET. His last press conference was August 9th.

From NBC's Kelly O'Donnell

Sources close to the presumptive campaign tell NBC News that Fred Thompson's fundraising is down "markedly." One claimed it has "slowed down big-time." The pace is described as a consequence of the delayed announcement to enter the race."The Friends of Fred, Inc." will report to the IRS its revenue by July 31st. Sources reveal to NBC News that number will be in the range of about $3 million. Five million dollars had been the talked-about June goal. Sources describe an early burst of donations in June and say the summer fundraising has fallen off. While additional fundraisers are planned, sources say the scheduling of fundraisers was "frozen" for a time while the team was going through some internal strains.

The Jeri Factor
Some sources describe the role of the presumed candidate's wife, Jeri, as vast and powerful.  Sources say "she's integrally involved in every decision" and that Fred Thompson has "set it up so everything goes through her." Critically, that was cast as "running it like a congressional campaign" and from the "kitchen table." 

Sources also describe Jeri favorably as smart, and that her level of involvement could be an asset. However, they also claim she is "reluctant" to shift to the eventual front-stage role she would have to assume as the candidate's spouse with her own events and public responsibilities. An interpretation of Jeri's role was described as a "scattershot management style" that "lacks prioritization."

At present, those close to the planning say Jeri is involved in hiring, salaries, schedule, office assignments at the two headquarters, and small details like the color of bumper stickers. Some sources defend her, adding that "it's easy to say she's controlling things."  Sources describe that she, like many in Washington, knows many people in politics. They acknowledge Jeri meets with and interviews senior staff candidates and is clearly a key adviser.

Another Staff Departure
Senior staffer J.T. Mastranadi is said to be out according to sources. Others near the Fred camp say word of Mastranadi's departure is "not accurate" and as of last evening "everything was fine." (But the Atlantic's Marc Ambinder has the campaign confirming Mastranadi's departure.)

Announcement Plans
Sources say September 4th in Nashville is the working plan, with Thompson possibly heading to South Carolina (if time permits) and then to New Hampshire for the September 5th GOP debate. The talk about a stop in Thompson's boyhood hometown seems unlikely. Yet sources acknowledge the launch could still change and that only a tiny group of advisers know the thinking.

Advisers contend it's better to have the "shake-ups and shake-downs now" than a month from now when they'd be in a "very different environment" with high scrutiny from media and other campaigns. One interpretation was, "a seamless pre-campaign does us no good if the official thing is a mess."

Structure And Organization
Roughly two dozen and "no more than 30" senior staffers are in place aside from those in state operations.

Advisers say Tom Collamore (who is gone now) was brought in for his organizational skills, and that he did set up the needed structure for two headquarters and hiring. Randy Enwright will be the political director and effectively running the operation. Former US Senator Spencer Abraham's role is being compared to the way Don Evans served George W. Bush as a confidant/counselor in 1999 and 2000.

The Fred team's internal research on the candidate to anticipate what opponents may dig up in their oppo shops has been going on for about a month and it's centered in Knoxville where the Senator's papers are housed.