Fred Thompson, a Republican registering well in national polls as he flirts with a presidential run, is the talk of this town's political elite.

It's a different story in early primary states where voters will choose the GOP nominee.

"You really don't hear much about him at all from people around here," said Irene Blom, chairwoman of the Republican Party in Marion County, Iowa. Added Paul Hogan, her counterpart in Georgetown County, S.C.: "He's mentioned a little, but there's no crescendo yet."

Should the actor and former Tennessee senator enter the race, he will be months behind his top competitors in building a campaign organization, raising money and securing support in key states.

Nevertheless, a Thompson bid could dramatically shake up the already wide-open field of Republicans. Conservatives who make up a significant part of the GOP base may be willing to rally around Thompson, who was known as reliably right-of-center in the Senate, given that they are underwhelmed with the leading GOP candidates. Those are former New York City Mayor Rudy Giuliani, Sen. John McCain of Arizona and ex-Gov. Mitt Romney of Massachusetts.

"It's not that conservatives have rejected any of them, it's that they haven't locked into them," said Steven Lombardo, a GOP strategist. Another, Chip Felkel, added: "The reaction to the mere idea of a Fred Thompson candidacy is significant in that he may truly be the only one that just about everyone can agree on."

The Thompson hype started last month when a cadre of Tennessee Republicans disclosed their behind-the-scenes efforts to recruit him. Thompson then acknowledged he was considering it, and seemingly overnight he went from zero percent in national popularity polls to trailing only Giuliani and McCain. Thompson is roughly even with Romney, who has been campaigning for months and raised $21 million.

In recent weeks, Thompson has appeared to move closer to a candidacy. The 64-year-old disclosed publicly that he was diagnosed with non-Hodgkin's lymphoma, a form of cancer, nearly three years ago but now is in remission. He also scheduled several high-profile public appearances, including a speech in California early next month.

On Wednesday, he met privately with some 50 House Republicans on Capitol Hill. Several gushed over him and promised endorsements should he run. They called him presidential, a leader, a proven conservative, an exciting prospect and "a breath of fresh air."

Emerging from the meeting, Thompson indicated he had not yet made a decision, but he also hinted at which way he may be leaning. He told reporters: "We had a good talk. I enjoyed it, and we'll be seeing some more of each other, I'm sure."

With his imposing stature and his deep Southern drawl, Thompson is perhaps best known for playing District Attorney Arthur Branch on NBC's drama "Law & Order." He has a contract for another year on the show if both he and the producers choose to exercise it. He also has had supporting roles on the big screen, including in the films "The Hunt for Red October" and "In the Line of Fire."

Thompson's political resume includes a stint as the minority counsel during the Watergate hearings and his election in 1994 to the Senate. During his eight-year tenure, he presided over a yearlong probe of alleged campaign fundraising improprieties — and established a reputation for griping about the long hours in the Senate.

His voting record is solidly conservative; he opposes abortion, gay marriage and gun control.

In Tennessee and in Congress, Thompson's backers insist that Republican voters nationwide are looking for someone who has conservative credentials and who can energize a dispirited party.

"Fred Thompson's the man" who fits that mold, said Rep. David Davis, R-Tenn.

He and other Thompson fans claim widespread support for him among Republicans in every region of the U.S.

"They are excited about seeing somebody step up to the plate who can make a difference for this country. They are excited about Fred Thompson," Rep. Gresham Barrett, R-S.C., said.

Rep. Jeff Miller, R-Fla., predicted "a groundswell of support" from the grass roots of the GOP should Thompson run and said: "People are ... thirsty for a leader, for a candidate that checks all the boxes and Fred Thompson is that person."

But for now, at least, GOP activists in each of the first three states to hold primary contests next year say voters there are focusing candidates who already have made their intentions clear. They say Thompson buzz is barely audible.

"I just don't see him catching fire at this point right now," said Al Simpson, chairman of the Lancaster County GOP in South Carolina.

What's more, these activists say, Republicans know very little about Thompson.

"Some people know he's done something but they don't know what," said John Fluit Jr., the Republican Party head in Lyon County, Iowa.

And, they say, voters don't know his politics.

"Does he meet the Republican positions on things? I have no clue," said Dick Barry, a state representative from Merrimack, N.H. "I don't know where he stands."