Updated

Sen. Lamar Alexander, R-Tenn., is stepping down as leader of the Senate Republican Conference, the third highest-ranking leadership position among Senate Republicans. He plans to leave the position in January.

"Stepping down from leadership will liberate me to spend more time working for results on the issues I care most about," Alexander said. "I want to do more to make the Senate a more effective institution so that it can deal better with serious issues."

Sen. John Thune, R-S.D., currently the number four Senate Republican as chair of the Policy Committee, has declared his intention to run to replace Alexander.

Alexander's announcement that he is stepping down from leadership comes very early and will be a surprise to his colleagues.

While he says the move frees him to solve problems, most see this as an attempt to avoid the embarrassing possibility that he will be beaten by National Republican Senatoral Committee Chairman Sen. John Cornyn,R-Texas, in the race to replace retiring number two GOP Sen. Jon Kyl, R-Ariz.

Many believe Cornyn is about to hand the reins of the Senate to Sen GOP Leader Mitch McConnell and he will be rewarded by his colleagues. On the Democratic side, Sen. Charles Schumer, D-N.Y. went from DSCC chair, after 2 victorious years, to having a special, powerful leadership post created for him.

Some Republicans have always thought Alexander was more moderate than his recent voting record would indicate, although he did vote to repeal ethanol subsidies and has indicated he could support more revenue increases for deficit reduction.

"I said to Tennesseans when I first ran for the Senate that I would serve with conservative principles and an independent attitude," Alexander said in a letter to his colleagues. "I will continue to serve in that same way. I am a very Republican Republican. I intend to be more, not less, in the thick of resolving serious issues. And I plan to run for re-election in 2014."

One Alexander aide called Alexander's decision today "the birth of a maverick."