DES MOINES, Iowa (AFP) — Republican White House hopefuls emboldened by the absence of front-runner Donald Trump jostled for the limelight at their final debate before the nomination votes begin, as the billionaire disrupted the showdown with his own controversial event.

Trump gambled big when he announced he was boycotting the debate because of a feud with Fox News over alleged bias against him, plunging the presidential race into uncharted waters just days before Iowans vote February 1.

The real estate mogul doubled down, in a game of political chicken, scheduling a rival event for military veterans at the same time as his party showcases its candidates to Iowa voters.

Straight out of the gate the seven debaters turned to the elephant-not-in-the-room, with top adversary Ted Cruz using Trump-like language to humorously belittle himself and rivals.

Republican presidential candidates Rick Santorum, left, and Donald Trump, center, laugh as they listen to Mike Huckabee during a campaign event on the campus of Drake University Thursday, Jan. 28, 2016, in Des Moines, Iowa. (AP Photo/Jae C. Hong)

Republican presidential candidates Rick Santorum, left, and Donald Trump, center, laugh as they listen to Mike Huckabee during a campaign event on the campus of Drake University Thursday, Jan. 28, 2016, in Des Moines, Iowa. (AP Photo/Jae C. Hong)

“I’m a maniac and everyone on this stage is stupid, fat and ugly. And Ben, you’re a terrible surgeon,” Cruz said, looking mischievously at retired neurosurgeon Ben Carson.

“We’ve gotten the Donald Trump portion out of the way,” he quipped.

All eyes are on the heartland state of Iowa, where 12 Republican candidates and three Democratic hopefuls including Hillary Clinton are vying for both bragging rights and momentum as the primary race heads next to New Hampshire, South Carolina and Nevada.

Trump had taunted Fox and his rivals, saying the debate would be a “total disaster” with low ratings.

The tycoon took the stage at his own event, just a few miles (kilometers) from his rivals, about 15 minutes after the debate began.

“I said I’m not going to do the debate out of respect for myself,” he said to cheers from the overflow crowd.

“But I love Iowa. I’m here.”

Ted Cruz, right, talks to Jeb Bush after a Republican presidential primary debate, Thursday, Jan. 28, 2016, in Des Moines, Iowa. (AP Photo/Chris Carlson)

Ted Cruz, right, talks to Jeb Bush after a Republican presidential primary debate, Thursday, Jan. 28, 2016, in Des Moines, Iowa. (AP Photo/Chris Carlson)

Adding to the spectacle, rival Mike Huckabee, the former Arkansas governor who is languishing in polls and attended an undercard event before the main debate, joined Trump at his veterans event, as did low-polling former senator Rick Santorum.

With Trump out of the way, Cruz and fellow Republicans launched into spirited debate about foreign policy and tackling the jihadist threat.

“I believe only with a strong America will we defeat this radical group called ISIS,” said Senator Marco Rubio, running third in national polls.

“If we capture any of these ISIS killers alive, they are going to Guantanamo Bay, Cuba.”

Senator Cruz defended himself when asked about a controversial call for “carpet-bombing” Islamic State group fighters, while not voting for President Barack Obama’s defense authorization request three years in a row.

“You claim it is tough talk to discuss carpet-bombing. It is not tough talk, it is a different fundamental military strategy than what we’ve seen from Barack Obama,” he said.

But even off the main stage, Trump’s shadow loomed large over the evening — and he was snatching many of the headlines.

Analysts have been riveted by the unexpected drama and disruption to the typical Iowa political playbook. The last major candidate to skip a pre-Iowa caucus debate was Ronald Reagan, in 1980.

“Wow. What a chess game,” Iowa State University political science professor Steffen Schmidt declared of the political theater.

Trump has accused Fox News, and especially debate moderator Megyn Kelly, of bias against him.

Shortly before the debate he told CNN that top Fox officials called him to apologize. Trump said he was mulling a last-minute appearance at the debate, but then his veterans event “took on a life of its own” and he felt compelled to appear there instead of the debate.

Trump has a genuine battle on his hands in Iowa with ultra-conservative Cruz who trails by about five percentage points in the RealClearPolitics average of recent Iowa polls.

Cruz, who has earned endorsements from key evangelicals and anti-abortion figures who tout his conservative and religious values, insists the race is winnable.

His team claims its ground game is second to none in Iowa, with 12,000 volunteers and staff blanketing the state.

Nationally, Trump keeps soaring. A recent CNN/ORC poll of Republican voters has Trump at 41 percent to 19 percent for Cruz, with more than two-thirds of Republicans saying they believe the billionaire developer will be the party’s presidential candidate.

Early Thursday, Cruz told Fox it was “stunning” that Trump refused to debate, challenging him to a one-on-one showdown.