Susan Davis reports on the presidential race.

http://blogs.wsj.com/washwire/2008/10/24/obamacans-prominent-republicans-line-up-behind-obama/

Since Colin Powell crossed party lines to endorse Barack Obama last Sunday, a steady stream of prominent Republicans have endorsed the Illinois senator over rival John McCain.

Former Massachusetts Gov. William Weld is endorsing Obama today at a press conference in Salem, N.H. Weld was a public supporter of Mitt Romney in the Republican primaries. In a statement, Weld called Obama a “once-in-a-lifetime candidate who will transform our politics and restore America’s standing in the world.”

On Thursday, former Minnesota Gov. Arne Carlson endorsed Obama at the state capitol. “I think we have in Barack Obama the clear possibility of a truly great president,” he said. “I would contend that it’s the most important election of my lifetime.”

Scott McClellan, a former spokesman for President George W. Bush, also endorsed Obama Thursday. USA Today reported that McClellan told CNN in a taping to be aired this weekend that Obama has “the best chance of changing the way Washington works.”

Ken Adelman, a prominent conservative on foreign policy matters announced his support for Obama on Tuesday, telling the New Yorker that his decision was based on temperament and judgment.

Adelman called McCain “impetuous, inconsistent, and imprudent; ending up just plain weird” in his handling of the U.S. economic crisis. He also was unsettled by McCain’s choice of running mate. “Not only is Sarah Palin not close to being acceptable in high office—I would not have hired her for even a mid-level post in the arms-control agency,” Adelman wrote.

UPDATE: Add Charles Fried, a Harvard Law professor and former Solicitor General in the Reagan administration, to the list of Republicans supporting Obama. Fried’s vote for the Democratic ticket is particularly harsh, as he was associated with the McCain campaign. Fried voted absentee for Obama this week, and informed McCain campaign general counsel Trevor Potter of his decision in a letter where he stated he could not support McCain in large part because of his selection of Palin as his running mate.

*To find out which newspapers are backing the presidential rivals, check out WSJ’s “Who Endorsed McCain?” and “Who Endorsed Obama?” pages.