In contrast to 2008, Democratic President Barack Obama cannot count on a wave of support for his re-election bid next year from well-known moderate Republicans.
Unhappy with Obama's handling of the economy, conservative backers from three years ago are either sitting on the fence or have thrown their lot in with Republican presidential hopefuls like Mitt Romney.
Known as Obamacons, moderate Republicans helped make the Democrat's case in 2008 that he was a new breed of post-partisan politician who would work with both parties. Obama's youth and the narrative of electing the first black president also attracted Republicans to make a rare show of support for a Democratic candidate.
They were actually drawn to the sense of hope that he represented. They also liked the fact that he was black, said David Gergen, who has served as an advisor to Republican and Democratic presidents.
Perhaps the most famous Obamacon was former Secretary of State Colin Powell, whose endorsement of Obama shortly before Election Day was a turning point in the 2008 campaign. Powell's staff says he has not decided who to support in 2012.
But others say their 2008 support for Obama was a one-off.
After years of bipartisan gridlock in Congress, high unemployment and a gaping budget deficit, Obama has lost some of his lustre.
Spending levels and tax policy are probably the most important issues for me at the federal level and things have not gone in the direction that I would favour in those departments, ex-Massachusetts Governor William Weld told Reuters. Governor Romney has a picture perfect textbook on those issues.
Weld, who backed Obama against Senator John McCain in 2008, said he would choose not just Romney over Obama in 2012 but some of the other Republican contenders as well if they won their party's nomination.
Support from influential moderate conservatives helped Obama win about 54 percent of the independent vote in 2008, according to exit polls, and he will need a strong showing among independents again next year to be re-elected. He was supported by 9 percent of Republicans in 2008.
I am a Republican and only voted for one Democrat in my entire life, and that was very much an anti-McCain vote. I thought Obama was going to be better than he turned out to be, said Kenneth Adelman, a former U.S. ambassador to the United Nations and adviser to a number of Republican presidents, including George W. Bush, Ronald Reagan and Richard Nixon.
Adelman is also backing Romney.
Some former Obamacons said they sympathized with the challenges Obama has faced, including strong opposition from congressional Republicans' and the poor U.S. economy. But they criticized the Democrat for not leading forcefully enough and not focussing harder on job creation.
There's a widespread sense of disillusionment. They thought he was going to be more centrist than he has proven to be, Gergen said.
Republican Arne Carlson, a former governor of Minnesota who backed Obama in 2008, criticized what he called Obama's lack of leadership. Carlson is still undecided but considering Romney.
I don't think he (Obama) has been strong enough or the kind of leader that this country needed. He always started out with 50-percent compromises. I think chief executive officers should execute strengths, Carlson said.
Bipartisan support is crucial for Obama, whose base of liberal support has been eroded by the tough economic climate.
It's always valuable for someone running for president ... to have as much bipartisan support as possible, presidential historian Robert Dallek said. At the end of the day, Americans are not so keen on ideologues, people who have such fixed positions that they can't see any virtue in the other side's point of view.
Obama's campaign said he continues to receive bipartisan backing. We have some Republican support, spokesman Ben LaBolt said.
Before Obama's 2008 victory, the most famous case of a presidential candidate winning substantial bipartisan support was Reagan's defeat of President Jimmy Carter in the 1980 election.
Despite grumblings about Obama's failure to bring down the unemployment rate quickly enough and shrink the budget deficit, some Obamacons have doubts about the current Republican field.
Charles Fried, a professor at Harvard Law School considered one of the most important U.S. conservative thinkers, voted for Obama three years ago after advising McCain's campaign.
He (Obama) is obviously highly intelligent, disciplined, well-informed and reasonable. But he has been disappointing as a leader and his decisions in the economic area have not been happy, Fried said.
Fried, who was Reagan's solicitor general, said he would support Republican long-shot candidate Jon Huntsman if he were the nominee, although he prefers the Democratic president over the rest of the Republicans.
He added that Romney had changed political positions over the years. He has shown that he is willing to say anything, and a person who is willing to say anything is willing to do anything, so I couldn't possibly trust him, Fried said.
And he said the rest of the Republican field were too extreme and in some cases close to nuts.
I'm not voting for any Republicans, said Francis Fukuyama, a 2008 Obama supporter who was a co-founder of the neoconservative movement and an author of the Reagan doctrine of resistance to the Soviet Union during the Cold War.
A few Obamacons remain firmly in the Democratic camp.
Jeffrey Hart, a founder of the conservative Dartmouth Review newspaper, said he supported Obama more than ever.
The Republican Party has declared war on the American middle class, he said in an email. While refusing to raise taxes on the upper 2 percent, the Republicans are trying to dismantle Medicare.
Hart was a speechwriter for Reagan and Nixon. But this is not that Republican Party, he said.
(Reporting by Eric Johnson in Chicago and Patricia Zengerle in Washington, writing by Patricia Zengerle; Editing by Alistair Bell and Paul Simao)