Texas Senator Ted Cruz opened the debate with a sarcastic impression of Trump's frequent insults of his opponents. (AFP)
Des Moines, United States:
2016 Republican presidential candidates strained to take advantage of a rare opportunity to step out of Donald Trump's shadow in Thursday night's presidential debate, after mocking the front-runner for boycotting the final contest before voting begins.
Texas Sen. Ted Cruz, who is locked in a tight contest with Trump in Iowa, opened the debate with a sarcastic impression of the real estate mogul's frequent insults of his opponents.
"I'm a maniac and everyone on this stage is stupid, fat and ugly," Cruz said, before thanking his fellow candidates for showing Iowa voters respect by showing up.
Former Florida Gov. Jeb Bush, a frequent target of Trump, said with a wry smile, "I kind of miss Donald Trump; he was a teddy bear to me."
Never one to go quietly, Trump was holding a competing rally elsewhere in Des Moines, an event his campaign said was raising money for military veterans.
"When you're treated badly, you have to stick up for your rights," Trump said in explaining he was skipping the debate because he felt Fox News had dealt with him unfairly. "We have to stick up for ourselves as people and we have to stick up for our country if we're being mistreated."
Thursday's debate comes four days before the Iowa caucuses kick off the 2016 nominating contest. Residents will choose among the Republican and Democratic candidates in the first of a series of state-by-state contests to choose delegates to each party's convention.
With their White House hopes on the line, the candidates moved quickly to cast themselves as best prepared to be commander in chief and take on terror threats emanating both from abroad and within the United States.
Florida Sen. Marco Rubio struck an aggressive posture, pledging that as president, he would go after terrorists "wherever they are. And if we capture them alive, we're sending them to Guantanamo." Rubio also stood by his previous calls for shutting down mosques in the US if there were indications that the Muslim religious centers were being used to radicalize terrorists.
Kentucky Sen. Rand Paul - back on the main debate stage after being downgraded to an undercard event because of low poll numbers earlier this month - warned against closing down mosques. A proponent of a more isolationist foreign policy, Paul also raised concerns about the US getting involved militarily in Syria, where the Islamic State has a stronghold.
The candidates largely sidestepped direct confrontations with each other, focusing some of their most pointed attacks on Democratic front-runner Hillary Clinton.
"She is not qualified to be president of the United States," New Jersey Gov. Chris Christie said. "What we need is someone on that stage who has been tested who has been through it."
Christie is part of a crowded field of more mainstream candidates who have struggled to break through in an election year where Trump, and increasingly Cruz, have tapped into voter anger with the political system. Party leaders have grown increasingly antsy for some of the more traditional candidates to step aside after the first contests to allow one to rise up and challenge for the nomination.
Asked whether the crowded establishment lane was putting Trump in position to be the nominee, Bush said, "We're just starting out. The first vote hasn't been counted. Why don't we let the process work?"
Trump pulled out of the debate this week, citing unfair treatment from host Fox News. He's feuded with the network for months, particularly anchor and debate moderator Megyn Kelly.
It's unclear whether Trump's unusual move will hurt his standing with Iowa voters. But his absence did give his rivals more time to make their case to voters.