The race for the 2012 Republican presidential nomination is in full swing, with GOP officials and activists across the country trying to decide which candidate to support. But at least one prominent Virginia Republican — George Allen — plans to stay on the sidelines.

Allen, the former governor and senator, was once considered a promising potential White House candidate himself. Now he’s running to get his old Senate seat back next year, most likely against former governor Tim Kaine (D), and he said in an interview Tuesday that he doesn’t plan to pick a horse in this White House contest until the primary is over.

“No, I don’t intend to endorse,” Allen said, adding that he had caught only a portion of Monday night’s Republican debate in New Hampshire.

Allen explained that “we’re building our own grass-roots organization here in Virginia,” one that he hoped would help the eventual GOP presidential nominee next November. Both parties expect the state to be a key battleground in the White House contest.

In the 2008 presidential contest — which Allen himself could have entered, had he not lost to James Webb (D) in 2006 — Allen initially backed former senator Fred Thompson (R-Tenn.) before eventually shifting his support to Sen. John McCain (R-Ariz.).

Allen’s pronouncement may not stop speculation to the contrary. The liberal blog Blue Virginia made the case Wednesday for why Allen could boost his standing with conservatives by endorsing Rep. Michelle Bachmann’s (R-Minn.) burgeoning campaign. But Allen doesn’t sound interested in lining up behind Bachmann or anyone else.