Washington (CNN) -- If case you had any doubts, don't -- Bill Clinton's fully on board President Barack Obama's re-election effort. "Barack Obama deserves to be re-elected president of the United States," the former president said Sunday night, as he joined the current officeholder at a fundraiser for the Obama re-election campaign. It was a very different story four years ago, when Clinton was the biggest and most vocal supporter of his wife, Hillary Clinton, in her historic battle against Obama for the Democratic presidential nomination. Clinton was a critic of then-Sen. Obama, arguing that the freshman senator wasn't ready to handle the duties of the Oval Office. Among Clinton's most controversial comments came when he challenged Obama's claim to be more against the Iraq War than Hillary Clinton.
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Four years ago, Bill Clinton was the biggest and most vocal supporter of Hillary Clinton
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Now, the former president will be a high-profile surrogate for President Obama
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Bill Clinton recently appeared in a buzzworthy Obama campaign web video
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Clinton can help Obama by reminding voters of better economic times
"There is no one with more economic credibility than President @placeholder -- so when he says President Obama will revive the economy and save the middle class, folks listen.