One can point out the high profile republicans and conservatives who have backed Obama as proof of his ability to unite opposing partys and views.
Joel Haugen, a Republican fighting a tough congressional race against the Democrats in Oregon, has fallen out with his party. The reason: his surprise endorsement of Barack Obama for the presidency.
"I believe in putting nation before party and my first priority is following my conscience with regard to what is best for America," Haugen said in a statement issued by his office today. "I have a huge amount of respect for John McCain, but I believe that he has more of a cold war mentality."
. The latest high-profile desertions include Scott McClellan, George Bush's former press secretary, who endorses Obama in a taped CNN programme to be broadcast this weekend, and William Weld, the Republican governor of Massachusetts from 1991 to 1997.
Weld, in a statement released today ahead of a press conference in New Hampshire, described Obama as "a once-in-a-lifetime candidate".
Last weekend, Bush's former secretary of state, Colin Powell, Obama's biggest Republican catch so far, publicly backed the Democratic candidate.
Arne Carlson, the Republican governor of Minnesota from 1991 to 1999, who wrote in the Minneapolis Star-Tribune yesterday: "The choice of governor Sarah Palin as a running mate, and the resultant shallow campaign based on fear and suspicion, looks frighteningly similar to the politics of Karl Rove [Bush's campaign strategist]."
He described Obama as having "the potential to become a truly great president".
The founders of Republicans for Obama include a former Iowa congressman, Jim Leach; a former Rhode Island senator, Lincoln Chafee, and a former Bush fund-raiser, Rita Hauser.
Another defector this week is Ken Adelman, a foreign policy adviser to Ronald Reagan, who told the New Yorker he would endorse Obama because of McCain's temperament, describing as weird his behaviour in response when the economic meltdown began.
Bruce Bartlett
Domestic policy advisor to President Reagan
Delbert Spurlock
Assistant Secretary of the Army under President Reagan