They've all been featured speakers at Democratic national conventions, only to become disaffected and address Republicans at their party gatherings.
Davis, who seconded Barack Obama's presidential nomination in 2008, will be among the headline speakers when Republicans gather in Tampa on Aug. 27-30, GOP chairman Reince Priebus announced today.
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A former congressman, Davis was once described as the "Obama of Alabama." He bolted the party in May charging that "the symbolism of Barack Obama winning has not give us the substance of a united country."
Last night, appearing on CNN, Davis said Obama should be "embarrassed" by Vice President Biden's controversial put people "in chains remark." Obama is standing by his No. 2.
Miller, then a Georgia senator, gave a fiery speech attacking Democratic presidential nominee John Kerry at the 2004 GOP convention. Miller slammed Kerry, a Vietnam veteran, on his national security record.
When Miller was Georgia's governor in 1992, he nominated Bill Clinton for president at the Democratic confab in New York City. His folksy speech included a line that President George H.W. Bush "just doesn't get it."
Lieberman, the 2004 Democratic vice presidential nominee, spoke in favor of his friend John McCain's presidential nomination at the GOP convention four years ago in St. Paul and campaigned extensively for the Arizona senator. The Connecticut senator had already switched parties to become an independent.
Ohio Sen. Rob Portman, who was vetted as a possible running mate for Mitt Romney, will also be a headline speaker at the GOP convention. Virginia Gov. Bob McDonnell, Louisiana Gov. Bobby Jindal, New Hampshire Sen. Kelly Ayotte and Florida Rep. Connie Mack will also have speaking roles.
