A Palin- and Paul-endorsee, Clint Didier is seeking the Republican nomination to challenge the incumbent U.S. Senator from Washington, Patty Murray. I say he's got a real chance.
An interesting three-way interview with Ron Paul can be found here. Paul mentions some of the very recent primary victories for his own endorsees, referencing the "amazing political climate" this election year; Didier, like Ron's son Rand, appears to have that broad "tea party" appeal to supporters of Sarah Palin and the Texas Congressman alike. There's nothing to make me think he can't pull off a primary victory and pose a serious challenge to Murray.
(Check out the conservative, Constitutional, ideas-driven candidate here.)