Rep. Jo Ann Emerson announced on Tuesday that she won’t run against Sen. Claire McCaskill (D-Mo.) in 2012.

“I’m honored to have been approached by so many encouraging people about the opportunity to serve our state in the U.S. Senate,” the Missouri Republican said in a statement. “I gave the matter a significant amount of consideration, talked it over with my family, and consulted with my trusted advisers and staff. We talked about what I can do as a junior member of the Senate and what I can do as a senior member of the U.S. House, and I decided the best possible way to serve Southern Missouri — as well as the entire state — is from my current post.”

Emerson, who was elected to replace her late husband in 1996, is the second House Member to pass on the Senate race. Rep. Sam Graves (R), who has represented northwest Missouri since 2001, decided not to run earlier this month. Missouri Republicans may have been encouraged to look at the race partially because the state will lose a House seat in reapportionment.

Emerson’s decision not to run leaves former state Treasurer Sarah Steelman and former Congressional candidate Ed Martin as the only two candidates in the GOP primary to face McCaskill. Former ambassador Ann Wagner, who lost a bid to be chairwoman of the Republican National Committee in January, may still get in the race.
 
“I think she’s still seriously looking at it,” said John Hancock, who served as executive director of the state Republican Party when Wagner was chairwoman. “I don’t think she’s in any particular hurry to make a decision.”
 
Former Sen. Jim Talent (R), who lost to McCaskill in 2006, was widely expected to run again, but in late January he announced he would not.

McCaskill is considered one of the most endangered incumbents up for re-election in 2012. Roll Call Politics rates this race a Tossup.

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