Sen. John ThuneJohn Randolph ThuneThreat of impeachment takes oxygen out of 2019 agenda Chances for disaster aid deal slip amid immigration fight Immigration fight imperils deal on disaster aid package MORE (R-S.D.) said he hasn't made any decisions about whether he'll run for president in 2012.

Thune, a member of the Senate Republican leadership, neither ruled in nor ruled out a run for the GOP nomination to challenge President Obama in two years, as speculation builds that he might be interested in a campaign.

"I haven't made any decisions beyond 2010," Thune said Tuesday night during an appearance on Fox News. "I haven't made any decisions about that."

Thune has long been talked about in Washington as a potential dark-horse candidate in 2012, but it was only recently he took actions to spark serious buzz about a bid to unseat Obama. Thune unveiled his own proposal to address the U.S. fiscal situation and has ramped up his travel schedule to help raise money and build support for Republican Senate candidates across the country.

Thune's campaigning, some of it in key swing and primary states, has led some observers to conclude the South Dakota senator is laying the groundwork for a White House bid.

"The reason I'm going to those places that you mentioned is because there are important Senate races there, and right now, my focus — and I think everyone's focus — should be on these midterm elections," he said Tuesday night, downplaying the rumors. "Because we have to do something to change the direction of this country. And the way to do that right now is to elect more Republicans to the House and to the Senate.

"I'm in a position, because I don't have an opponent in South Dakota this year, to have some more time and availability to get out and help some of my colleagues," Thune added in regard to his recent travel. "Really, I think that's what you can read into this — that I want to improve our numbers in the Senate."