Bob Bennett (Utah)
Senator Robert Bennett has won re-election by landslides since he was first elected to Congress's upper chamber in 1992. But this time around, he could see a tough challenge from former Juab County attorney David Leavitt, brother of Mike Leavitt, a former Utah governor and secretary of Health and Human Services under George W. Bush. Leavitt is upset with a series of moderate stances Bennett has recently taken: in 2005 he opposed a constitutional amendment banning flag-burning, and that same year he was one of the few high-profile Republican supporters of Bush's immigration reform. And worst of all in conservatives' eyes, Bennett signed on as a co-sponsor of Democratic Senator Ron Wyden's alternative bill for universal health care. The bill has never gone anywhere, but the damage to Bennett has already been done.