With two weeks to go until the first contest of the 2016 presidential race, Republicans who fear their party has been hijacked by the likes of Donald Trump and Ted Cruz found little to comfort them in the latest debate.

Both candidates, one a billionaire developer with no political experience and the other a U.S. senator from Texas with a reputation for clashing with his Washington D.C. colleagues, stood center stage Thursday night and, for the most part, dominated the proceedings.

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More mainstream hopefuls such as former Florida Governor Jeb Bush, New Jersey Governor Chris Christie, Ohio Governor John Kasich, and U.S. Senator Marco Rubio from Florida were left nipping at their heels and squabbling among themselves.

Trump, 69, and Cruz, 45, whom opinion polls have locked in a tight struggle to win the Feb. 1 Iowa caucuses, clashed at several points, befitting their leading-men status. The left little room for rivals trying to hurriedly close the gap before voting begins to choose the party's nominee for November's general election.

All of it left some Republicans worried that time to stop Trump or Cruz from seizing the inside track on the nomination was evaporating and that the establishment candidates were doing little to slow either man’s momentum.

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“They are digging themselves a bit of a hole,” said Fergus Cullen, the former chairman of the New Hampshire Republican Party. “It’s entirely possible the final two candidates will be Trump and Cruz, and people like me will be despondent.”

New Hampshire holds its primary about a week after Iowa’s and perhaps offers the best chance for a more moderate option to surface as a prime challenger. Iowa Republicans historically tend to favor more conservative candidates.

But in New Hampshire right now, “the mainstream Republicans are as splintered and scattered as ever,” Cullen said, leaving open the possibility that Trump could win that state as well.

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Trump and Cruz dominated social media mentions in the debate. And according to Google’s analytics, which tracked audience responses to the debate, Trump and Cruz came out as the winners.

“More and more, this is coming down to a two-man race. The polling, the support, it is more and more looking like it is Donald Trump and me,” Cruz said in an interview on the Fox Business Network after the debate.