The stunning Texas victory of Ted Cruz, a young Tea Party-backed Republican over an establishment candidate vying for a Senate seat, has already so emboldened the insurgent conservative movement that activists are warning Mitt Romney he had better get on board.
"These guys [newly elected Tea Party candidates]" are going to force Romney to the right," said Amanda Shell, a spokeswoman for Tea Party group Freedom Works. "That is our entire mission."
Cruz won the Texas Republican primary Tuesday night. In Texas, winning the Republican nomination is a virtual lock on a Senate election.
His victory is the latest in a string of Tea Party candidates to tap into anti-establishment frustration within the Republican Party and overcome the steep odds and deep pockets of more mainstream candidates.
Riding a wave of recent successes in the House and now also the Senate, Tea Party groups are eyeing the possible control of both chambers, a prospect, they say, would force Romney, were he to win the presidential election in November, "to move to the right."
"If we can elect a really conservative House and Senate that will force Romney to go along with our bold conservative agenda," Shell said. "He's going to have to really, really go to the right. He'll be working with guys in the House and Senate. He won't be able to get away with too many middle of the road policies, especially on things like the deficit."
Capitol Hill observers note that many newly elected and Tea Party-backed legislators want to remove the taint of Republican-back government spending during the Bush administration. So dedicated are they to the goals of cutting spending, shrinking the deficit and keeping government small, that they are motivated by ideology and not party loyalty.
"It's not going to be a Romney driven presidency," Norman Orenstein, a researcher at the conservative think tank AEI recently told ABC News. "It's going to be a Congressional, conservative, Republican driven presidency from Congress."
But one adversary turned supporter, said Romney need not worry about taking orders from the Tea Party because both had the same, not opposing agendas.
"If the Tea Party says it wants Romney to move right, I think, that's were Romney is going anyway," Newt Gingrich, former House speaker and presidential candidate, told ABCNews.com.
"Romney has endorsed the Ryan budget plan, opposed tax increases, and indicated he supports the full repeal of Obamacare. That's a pretty activist opening day," Gingrich said.
"You have to think of Romney as having a foot in the Tea Party and a foot in the establishment," he said, adding, "that's right where the Republicans want him."
Requests for comment from the Romney campaign were not returned.