Sarah Palin has begun to get on the nerves of Republican senators who say the former GOP vice presidential nominee is taking her own White House aspirations entirely too seriously. But those same senators may have their eye on a 2012 White House run or be friends with senators with presidential ambitions. And Palin, who does not have a lot of Washington connections, energized the party’s grass roots in 2008 while bucking the D.C. establishment, leaving much of the party’s elite grumbling about her appeal to the conservative base. Several GOP senators offered searing criticism of the Alaska governor when...