DES MOINES, Iowa — Texas Sen. Ted Cruz, a fiery conservative loathed by his own party’s leaders, swept to victory in Iowa’s Republican caucuses Monday, overcoming billionaire Donald Trump and a stronger-than-expected showing by Florida Sen. Marco Rubio. Among Democrats, Bernie Sanders rode a wave of voter enthusiasm to a virtual tie with Hillary Clinton, long considered her party’s front-runner.

Cruz’s victory over Trump was a testament to his massive get-out-the-vote operation in Iowa and the months he spent wooing the state’s influential conservative and evangelical leaders.

“Iowa has sent notice that the Republican nominee and next president of the United States will not be chosen by the media, will not be chosen by the Washington establishment,” Cruz said.

His comments were echoed by Sanders, underscoring the degree to which voter frustration with the political system has crossed party lines in the 2016 campaign.

“It is too late for establishment politics and establishment economics,” said Sanders, who declared the Democratic race a “virtual tie.”

Clinton took the stage at her own campaign rally saying she was “breathing a big sigh of relief” but with the Democratic race too close to call. Aware that even a slim victory over Sanders would reinvigorate questions about her candidacy, she foresaw a long race to come.

“It is rare that we have the opportunity we do now, to have a real contest of ideas, to really think hard about what the Democratic Party stands for and what we want the future of our country to look like,” Clinton said.

Trump has shaken the Republican Party perhaps more than any other candidate, though he was unable to turn his legion of fans into an Iowa victory.

He sounded humble in defeat, saying he was “honored” by the support of Iowans. And he vowed to keep up his fight for the Republican nomination.

“We will go on to easily beat Hillary or Bernie or whoever the hell they throw up,” Trump told cheering supporters.

For Clinton’s supporters, the tight race with Sanders was sure to bring back painful memories of her loss to Barack Obama in 2008. Her campaign spent nearly a year building a get-out-the-vote operation in Iowa yet still seemed to be caught off guard by the enthusiasm surrounding Sanders.

A self-declared democratic socialist from Vermont, Sanders drew large, youthful crowds across the state with his calls for breaking up big Wall Street banks and his fierce opposition to a campaign finance system that he says is rigged for the wealthy.

With the race too close to call, Sanders’ aides said they had been told by the Iowa Democratic Party that it did not have results from several precincts and had asked the campaigns to help get the missing information. The party said it was awaiting results from a “small number of outstanding precincts” and had reached out to the campaigns for help contacting the chairs from those sites.

Cruz modeled his campaign after past Iowa Republican winners, visiting all of the state’s 99 counties and courting evangelical and conservative leaders. While candidates with that portfolio have often faded later in the primary season, Cruz hopes to ride his momentum to the nomination.

Trump took second place, but Rubio, favored by more mainstream Republicans, gave him a battle even for that.

“We have taken the first step, but an important step, to winning the nomination,” Rubio said at a campaign rally in Des Moines.