Former South Dakota Lieutenant Governor Steve Kirby will not run for the Republican nomination against Democratic Senator Tim Johnson, he told the Sioux Falls Argus Leader today. Kirby's exit, after weeks of considering the race, leaves State Rep. Joel Dykstra and former Ambassador Bert Tollefson as the only Republicans who have announced they will challenge Johnson.

Kirby had been heavily recruited by the National Republican Senatorial Committee, whose chair, Nevada Senator John Ensign, hinted at his candidacy in an interview with Politics Nation in January. Kirby would have been stronger than either of the remaining candidates, a fact that led national Democrats to launch shots at him even as he explored a race.

The loss of the last-ditch GOP hopeful leaves Johnson in strong position to win a third term after winning his last election by just over 500 votes, over now-colleague John Thune. Though South Dakota votes overwhelmingly Republican in presidential contests, Johnson and Rep. Stephanie Herseth Sandlin are hugely popular with voters, as is Thune.

Barring the ability to seriously compete in South Dakota, national Republicans are left with Louisiana as their lone strong takeover target. Though the party remains cautiously optimistic about New Jersey, the loss last week of their top recruit in that state due to medical issues virtually assured Senator Frank Lautenberg of a weaker, more conservative opponent in a generally safe Democratic state.