DES MOINES  — Ted Cruz sealed a victory in the Republican Iowa caucuses Monday, winning on the strength of his relentless campaigning and support from his party’s most conservative wing.

The victory in the first Republican primary contest ensures that Cruz will be a force in the presidential race for weeks to come — if not longer. The first-term Texas senator now heads to New Hampshire as an undisputed favorite of the furthest right voters, a position of strength for drawing in evangelical voters and others who prioritize an abrupt break with President Barack Obama’s policies.

Perhaps most importantly, Cruz’s win denied Donald Trump a huge opportunity to gain momentum heading into New Hampshire. Trump parlayed his fame as a billionaire real estate mogul and reality television star into large rallies and national poll numbers that before Monday night had established him as the Republican front-runner.

But Trump, who campaigned on the concept of being a winner, failed to come in first. He was battling for position with Florida Sen. Marco Rubio, who has worked for a strong enough showing to help cement his status as the favorite of mainstream Republican voters who worry that Cruz and Trump are too caustic to win the November general election.

The Texas senator visited all 99 of Iowa’s counties — and convinced voters that he would deliver on promises to end Obamacare and use extensive aerial bombing campaigns to stop Islamic State militants in the Middle East.

Cruz backer Shane VanderHart, 43, of Pleasant Hill, Iowa, said he believes Cruz will actually repeal the health insurance program introduced by Obama in 2010, a longtime pledge by Republican candidates.

“When he says he’s going to repeal it, I believe him because he’s followed through on his campaign promises in the Senate,” VanderHart said.

Michael Napuunoa, 25, an electrician from Des Moines, said he liked Cruz’s promise to strengthen the military and fight terrorism.

“He may not be as aggressive as Trump,” Napuuona said. “But I don’t want a hothead. I want a man who’s going to get the job done and not kill everyone in the process.”

The Iowa results have already narrowed an unusually crowded Republican field, with a number of candidates struggling to achieve the turnout needed to continue. Former Arkansas Gov. Mike Huckabee ended his campaign Monday night.

GOP caucus-goers were overwhelmingly motivated by their frustration with the government. Nine out of 10 Republican voters said they’re angry or dissatisfied with Washington.

Among conservative caucus-goers, the entrance poll showed Cruz was the top choice. Trump fared best with moderates. Caucus-goers who said they were somewhat conservative were split between Rubio and Trump.

Monday’s contest provided hard evidence that Trump could not easily turn the legion of fans drawn to his adversarial populism into voters. The scope of the billionaire’s organization in Iowa was a mystery, though Trump himself had intensified his campaign schedule during the final sprint.

Meanwhile, former Florida Gov. Jeb Bush, New Jersey Gov. Chris Christie and Ohio Gov. John Kasich barely register in recent Iowa polls. The governors are banking instead on strong showings in New Hampshire’s Feb. 9 primary to jumpstart their White House bids.