An earlier-than-expected race for three posts in the Senate GOP leadership lineup kicked off in earnest Thursday after Sen. Kay Bailey Hutchison (Texas) announced she was vacating her post next year as the party’s Policy Committee chairwoman.

Conversations were quickly under way among the 49 Republican Senators over who would run for the No. 4 slot, as well as for the National Republican Senatorial Committee chairmanship and the Conference vice chairmanship.

Included in the initial list of possible successors to Hutchison at the policy post are her home-state colleague and Conference vice chairman, Sen. John Cornyn, who is next in line. Others being mentioned are NRSC Chairman John Ensign (Nev.) and Sen. John Thune (S.D.), the Chief Deputy Minority Whip. The NRSC job has caught the attention of Cornyn and Sen. Norm Coleman (Minn.), while Cornyn’s current job as vice chairman could spark a flurry of interest, including from Thune or Ensign, as well as other up-and-comers such as Sens. Richard Burr (N.C.), Mel Martinez (Fla.), Johnny Isakson (Ga.) or Jim DeMint (S.C.).

“I think they are already starting to work it,” a senior Republican Senate aide said. “I think they started after lunch today.”

Hutchison told her colleagues the news at a private Member luncheon that she would not run for a second term as Policy Committee chairwoman, instead saying she wants to focus on other opportunities at home. Hutchison, who has said she will not seek re-election for the Senate in 2012, is expected to run for governor in 2010, and GOP sources say she is planning to set up an exploratory committee for that office in the next term. Texas Gov. Rick Perry (R) has not said whether he will run again.

Her decision to step out of the Republican Senate hierarchy in the 111th Congress came as no surprise, but the timing was earlier than most GOP Senators anticipated. Senate intraparty leadership elections are set for mid-November, after what’s expected to be a difficult Nov. 4 for the GOP.

The top three Republican Senate leaders — Minority Leader Mitch McConnell (Ky.), Minority Whip Jon Kyl (Ariz.) and Conference Chairman Lamar Alexander (Tenn.) — are expected to be safe in their positions at least for the next two years, regardless of the general election results. But Hutchison’s decision not to run for leadership, along with promises from Ensign to leave his NRSC job, have assured some shuffling within the lower ranks.

Also, if Cornyn runs successfully to replace either Hutchison or Ensign, his job as Conference vice chairman would be up for grabs. Sources close to the Texas Senator say he does not plan to run for the vice chairmanship again and in the coming weeks will decide whether to seek the policy position — for which he is likely to have the advantage — or NRSC chairmanship.

The other leading contender for the NRSC post next year is Coleman, a first-term Senator who unsuccessfully sought the post in 2006. Coleman, however, must first clear the hurdle of securing another six years against Democrat Al Franken this November.

In a brief interview Thursday, Coleman brushed aside talk of his future in the GOP leadership, only saying: “I’m just focusing on the people of Minnesota and my re-election on Nov. 4.”

Thune has long been rumored as a future candidate for leadership but has yet to mount a formal bid. On Thursday, he said that if Hutchison’s announcement “opens up opportunities for some new people, that’s certainly something I would give consideration to.”

As for the other prospective policy chairman candidates, Ensign already has ruled out a second term at the NRSC. Through a spokesman, Tory Mazzola, Ensign said he is considering the job.

“Yes, Sen. Ensign is interested, but right now he remains 100 percent committed to the task at hand at the NRSC,” Mazzola said. “He is simply interested.”