[WASHINGTON] Donald Trump has extended his lead in the Republican presidential nomination race amid a fresh bout of controversy over his remarks about Muslims, while Hillary Clinton has consolidated her lead among Democrats, a poll showed Wednesday.
Less than two months before the first state-wide votes to determine the presidential nominees, Mr Trump was his party's undisputed leader, backed by 27 per cent of registered Republican voters, while his closest challenger for months, retired neurosurgeon Ben Carson, has faded to third place, according to the Quinnipiac University survey.
Freshman Senator Marco Rubio of Florida has surged into second with 17 per cent, while Mr Carson is tied for third with Senator Ted Cruz of Texas at 16 per cent. Former Florida governor Jeb Bush languishes in fifth place with five per cent, while no other candidate is above three per cent.
Quinnipiac conducted its poll last week. Its Republican figures have a margin of error of 3.8 percentage points; the error margin for the Democratic polling is 4.1 percentage points.
Mr Trump has faced fierce criticism for several remarks he has made in recent weeks, including saying "thousands" of Muslims in New Jersey cheered when the World Trade Centre collapsed in the 9/11 attacks of 2001, a claim that has been widely debunked.
"It doesn't seem to matter what he says or who he offends, whether the facts are contested or the 'political correctness' is challenged, Donald Trump seems to be wearing Kevlar," Quinnipiac assistant poll director Tim Malloy said in a news release detailing the results.
Mr Trump, who was at 24 per cent one month ago, has topped nearly all Republican polls since July.
Among registered Democratic voters, Mrs Clinton has risen to 60 per cent support, double the backing of her nearest rival, Senator Bernie Sanders of Vermont, at 30 per cent, according to Quinnipiac.
Former Maryland governor Martin O'Malley registers just two per cent in the much smaller Democratic field.
Mrs Clinton, bolstered by Vice President Joe Biden's decision not to seek the nomination, has appeared more confident on the campaign trail.
Mr Sanders, a self-described democratic socialist, has sought to seduce voters on the left, but his campaign, which soared in the summer, appears to have come down to Earth and is plodding along with little gain against Mrs Clinton.
The first state-wide vote in the primary process to determine the parties' nominees occurs in Iowa on February 1, followed by New Hampshire on February 9.