REUTERS - Republican presidential candidates Marco Rubio and Ted Cruz emerged as the strongest challengers on Wednesday to insurgent front-runners Donald Trump and Ben Carson, in a fiery debate that may have marked a new phase in the 2016 race.
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With time running short until the first nominating contest in three months, the 10 Republicans in the evening's main debate were anxious to stand out. They frequently talked over each other and the moderators in a debate laced with personal attacks and clashes over tax policy.
In a dominating performance, Rubio, the U.S. senator from Florida, swatted away Jeb Bush when the former Florida governor attacked his attendance record in the Senate.
“Just resign and let someone else take the job,” Bush said, in response to a question about an editorial in a Florida newspaper that blasted Rubio for having missed about one-third of his Senate votes this year.
That prompted Rubio to scold Bush for aligning himself with the liberal media. The only reason Bush was making it an issue, Rubio said, was “because we’re running for the same position, and someone has convinced you that attacking me is going to help you.”
The exchange came on a night of heated clashes among candidates fighting to catch Carson and Trump, two upstart candidates who have tapped into voters' frustration with the Republican party's establishment. The latest Reuters/Ipsos poll showed Carson, a retired neurosurgeon, and Trump, a celebrity real estate developer, in a dead heat.
In a sign that the unpredictable Republican race might be entering a new phase, Trump and Carson, while not stumbling, were often eclipsed by Rubio and Cruz during the two-hour debate at the University of Colorado campus.
"Rubio won tonight with wit, good humor, great one-liners and substance," said Ari Fleischer, who was press secretary to former President George W. Bush.
Cruz, a U.S. senator from Texas, scored by turning to a well-worn page in the Republican playbook: Attacking the news media. He ignored a question on the debt limit to criticize the CNBC debate moderators for the questions they had posed to candidates.
"The questions that have been asked so far in this debate illustrate why the American people don't trust the media," he said. "This is not a cage match. How about talking about the substantive issues?"
The crowd gathered in an arena in the foothills of the Rocky Mountains roared its approval.
Cruz's response laid bare that a debate that was supposed to be all about the U.S. economy had strayed from the theme repeatedly, so much so that the Republican National Committee took the extraordinary step of criticizing the TV network that broadcast it.
"The performance by the CNBC moderators was extremely disappointing and did a disservice to their network, our candidates, and voters," said RNC Chairman Reince Priebus.