As Republicans aim for control of the Senate in the 2014 general elections, they must first run some gut-wrenching gauntlets to get through their primaries relatively unscathed, and emerge with a nominee who can win in November.Given the crowded GOP field of Senate nominee contenders and the contentious nature of recent primaries, that could be a tall order. That’s why U.S. Sen. Lamar Alexander is running so hard to keep from getting “primaried” from the right by state Rep. Joe Carr, who has portrayed Alexander as an out-of-touch “career politician.” To read Carr’s campaign literature and hear his sound-bite rhetoric, you’d think Lamar has gone “liberal” on us.