That's not to say Romney completely ignores Bush, either. On the March day when he was endorsed by Jeb Bush, Romney credited the former president with averting another Depression in 2008. Bush's father, George H.W. Bush, endorsed Romney little more than a week later.
"I keep hearing the president say that he's responsible for keeping America from going into a Great Depression," Romney said of Obama. "No, no, no. That was President George W. Bush and (Treasury Secretary) Hank Paulson that stepped in and kept that from happening."
There are no rules for using former presidents in political campaigns, nor are potential successors bound to embrace them.
But Obama is keeping his Democratic predecessor closer this time around.
Democrat Bill Clinton had a muted role in the 2008 general election after the nasty primary fight between his wife, Hillary Rodham Clinton, and Obama. But Obama has signaled this year that he intends to fully embrace the popular former president — and take advantage of his political strengths. A prolific fundraiser, Clinton recently appeared with Obama at a money event near Washington. He also has a prominent role in Obama campaign videos.
Clinton was sidelined while still in office in 2000 when Vice President Al Gore kept him at bay after the Monica Lewinsky scandal.
History doesn't offer much precedent for handling former presidents at party conventions, either.
Clinton and Jimmy Carter gave speeches on the first day of the 2004 Democratic convention. In 2000, the elder Bush and Gerald Ford were present when George W. Bush was nominated, but neither man spoke. In 1996, both Ford and George H.W. Bush spoke.
Four years ago, McCain kept Bush at a distance after an awkward joint appearance in the White House Rose Garden. McCain had challenged Bush for the nomination in 2000 and didn't endorse him after Bush prevailed.
During his convention speech in 2008, McCain spoke the Bush name only once — in reference to Laura Bush.
Associated Press Deputy Director of Polling Jennifer Agiesta contributed to this report.
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