Mitt Romney now clear favourite to win Republican presidential nomination after winning three out five opening contests
Newt Gingrich scrambled on Sunday to keep his presidential bid alive after a heavy defeat in the Nevada caucus, vowing as a conservative to hound frontrunner Mitt Romney to the last.
But the exit polls in Nevada showed Gingrich's support among the very conservative and among evangelicals bleeding away, as Republican voters of various shades latch on to Romney as the best prospect of beating Barack Obama.
Romney took 48% in Nevada, a more than twice Gingrich's 23%. Ron Paul was not far behind with 18.5%, and Rick Santorum fourth with 11%.
Nevada establishes Romney as the clear favourite for the nomination, coming after his decisive win in Florida and taken with what is expected to be a run of wins in six other states scheduled to vote this month. He has now won three out of five opening contests.
Gingrich abandoned the usual post-results speech for a press conference during which he angrily accused Romney of running a ruthless and dishonest campaign, dismissing rumours he was about to quit. Gingrich said he would fight all the way to the nomination convention in Florida in August, arguing that his more conservative philosophy would ultimately appeal over Romney's "moderate" policies.
Elaborating on NBC's Meet the Press on Sunday, Gingrich said Romney's record on abortion, gun control and taxes would disqualify him in the minds of conservatives.
"My goal over the next few weeks is to draw a very sharp distinction between Romney's positions, which the Wall Street Journal described as timid and, in terms of tax policies, as being like Obama."
"The challenge is to say: do you really want to go in to a fall election with a moderate candidate? The last two times we nominated a moderate – 1996 and 2008 – we lost badly. A conservative candidate can offer a much greater contrast with President [Barack] Obama."
Gingrich acknowledged that the coming votes would be difficult, but said that his goal is to keep the campaign alive until Super Tuesday on 6 March when several conservative states are among 10 having contests, and he is "in much more favourable territory".
"We want to get to Georgia, to Alabama, to Tennessee, to Texas. We believe by the time Texas is over [in April], we'll be very, very competitive in delegate count. The key from my standpoint is to make this a big choice campaign," he said.
But Gingrich faces a struggle to reestablish himself as a credible candidate. Exit polls showed support falling away among conservatives, evangelicals and Tea Party supporters who delivered him victory in South Carolina and Florida; in Nevada they swung heavily towards Romney.
However, the polls also showed little enthusiasm for Romney. Four out of 10 Republican voters in Nevada said they were principally focused on getting Obama out of the White House, suggesting many are prepared to compromise some ideological beliefs to back the man they best believe can do that. Romney is also more trusted on the economy.
In Nevada, Gingrich painted himself as the anti-establishment candidate, taking on not just Washington but the leadership of his own party.
"I was surprised by the degree to which the establishment has closed ranks and made quite clear that they're desperate over the prospect of a Gingrich presidency," he said.
Gingrich may also find his single most important source of support drying up. The New York Times reported that the billionaire casino magnate Sheldon Adelson, who has spent at least $10m on attack adverts for Gingrich, has he will back Romney if it is clear he will be the nominee.
Gingrich previously revived his campaign with strong performances in television debates, which helped his victory in the South Carolina primary, before Romney hit back hard in debates in Florida. However, there are no more debates until next month.
In his victory speech in Las Vegas, Romney, a former governor of Massachusetts, referred to his having won in Nevada during what turned out to be his failed bid for president four years ago, but said that this time it would be different: "This time I'm going to take it to the White House."