During this election cycle, the Tea Party has been the Republican Party's single most important group.
But there's a debate about how big the movement's impact will be inside the Congress -- and whether it will be positive or negative for the GOP in the 2012 cycle, which, of course, is already under way.
As many as 60 of the new Republicans in the House and about half a dozen in the Senate were backed by the Tea Parties, and their potential clout may exceed their numbers.
John Boehner, the man who will be speaker, knows it -- and he's promised a mind meld with the new Tea Party freshmen.
"I don't see any problems incorporating the members of the Tea Party along with our party," he said, "in the quest that's really the same."
But maybe the Tea Parties don't want to be "incorporated."
On Election Day, South Carolina Sen. Jim DeMint, who bucked Republican leaders to endorse Tea Party candidates all over the country, wrote an op-ed in The Wall Street Journal warning new conservative senators not to get "co-opted" or coerced by the establishment club.
"Put on your boxing gloves," he told them. "The fight starts today."
In an interview Wednesday, DeMint said there won't be any tension as long as the Republican leaders adhere to the Tea Party's agenda.
"If they're true to the people who elected them, I think we're going to work well and move our conference more in a conservative direction that I think reflects where America is right now," he said.
DeMint's first test: a vote to permanently ban earmarks -- special interest spending tucked into appropriations bills without an up or down vote.
"I think as soon as we dispense with the parochial earmark system, just about every Republican'll be on the same page, working on some bold reforms," he said.
It's possible an earmark ban could be enacted in the House, but Senate Republican leader Mitch McConnell has been cool to the idea.
Former Republican Rep. Tom Davis says the GOP leadership has to handle the Tea Party caucus carefully.
"That's why Eric Cantor's saying, 'We're going to repeal the health care bill.' They have the votes, probably, to repeal the health care bill in the House. It's not going anywhere in the Senate, the president isn't going to sign it, so they're not going to repeal it," he says. "But at least they get to show the flag because they're going to have to do some other things that are not going to be very popular with the Tea Party."
For example, he says, "They have to raise the debt ceiling, unless you want to ... stop the government from writing checks."
And that may not sit well with the Tea Party's grass roots. At a recent gathering of Tea Party activists in Washington, everyone said they wanted the new health care law repealed or defunded.
Jamie Radtke of the Virginia Tea Party Federation expects more: "They've got to look at ways to cut spending. And it's got to happen in real, measurable ways. Not the, you know, $100 million here, $50 million here. There's got to be a serious overhaul of how they're doing business up there."
Dana Kitchen of the Richmond Tea Party is very clear about what he wants the new Republican majority to deliver.
"I expect, first and foremost, a balanced budget amendment," he says. "As far as adding to the deficit, I would like to see no more new appropriations until we sort out all the mess that's in front of us now."
Dana Lash of St. Louis isn't worried about being disappointed by the new Republican Congress because, she says, they are on probation.
"I expect them to be very reliable. That's what they're there for," she says. "They're not there to institute their own agenda. They are there to institute our agenda. And with the exact same fervor that we went after the candidates that we're not very happy with now and got them out of the primaries, we can go after them, too."
And they will. Plans are already under way for primary challenges to Republicans up for re-election in 2012, such as Sens. Richard Lugar, Olympia Snowe and Bob Corker.
President Obama's top political strategist, David Plouffe, thinks in two years the Tea Parties will pull the GOP out of the mainstream.
"If you're a moderate Republican thinking about running for a primary, you're not going to think about it very long because it's clear that you're not going to be able to win," he says. "So the Republican nominees, I would argue, from president all the way down to local office, are going to be much more conservative, I think, as a group than they were in 2010."
Too conservative, the White House team dearly hopes, to defeat the president in 2012.
As for the 2012 Republican presidential primaries -- the emergence of the Tea Parties has turned that hierarchical ritual upside down, says former House Speaker Newt Gingrich, who is considering a presidential bid of his own.
"It's a much more complicated process than people think," he says. "None of the folks in the Washington establishment could have dreamed in January that seven insurgents would beat the establishment in senatorial primaries. So why would they think they understand the 2012 process?"
Gingrich predicts there will be an unofficial Tea Party primary and he's already getting ready to compete in it by traveling the country, meeting with grass-roots activists.
All this is causing heartburn for the Republican establishment. There's a raging debate inside the GOP about whether failed Tea Party-backed candidates -- like Sharron Angle in Nevada, Christine O'Donnell in Delaware and Ken Buck in Colorado -- ended up denying Republicans control of the Senate. And there's talk about trying to stop the rise of Tea Party favorite Sarah Palin, who many Republicans fear could cost the GOP the White House if she runs in 2012.
It's the kind of talk that has to be kept off the record, of course -- for fear of sparking a backlash from the Republican Party's most important and unpredictable constituency.