Washington: As rival Republican presidential candidates looked for ways of combating a surging Donald Trump, a new poll suggested that party supporters increasingly think he was their best bet for the 2016 presidential race.

With confidence fading in traditional politicians like Jeb Bush and Wisconsin governor Scott Walker, 39 percent of Republican voters viewed Trump as their best shot at winning the presidency, according to a New York Times/CBS News poll. This compared with 26 percent who favoured him in a CBS survey in August. Only 15 percent said they would not back him as the party\'s nominee.

Despite some reservations about Trump, the real estate mogul appears to be gaining acceptance as a possible nominee, suggested the poll released on the eve of second presidential debate Wednesday at the Ronald Reagan Presidential Library in Simi Valley, California.

Neurosurgeon Ben Carson, another outsider, has also risen to 23 percent from just 6 percent early last month. Trump draws 27 percent support in the new poll, compared with 24 percent in August.

Among Democrats, uneasiness with Hillary Clinton is growing and creating a possible opening for Vice President Joseph Biden, as he mulls a presidential run, the poll found. Her lead over self-proclaimed socialist Senator Bernie Sanders has shrunk from 41 percentage points to 20 points. Nearly six in 10 Democrats said they wanted to see Biden join the race.

Meanwhile, Trump kept up his tirade against illegal immigrants at a campaign event in Iowa saying, \"We have many problems in our country. One of them is immigration.\"

\"There\'s tremendous crime. There\'s tremendous drugs pouring across the border ... going to Chicago, going to New York, going to LA.\"

\"We get the drugs, they get the money. The drug cartels are going wild; they cannot believe how stupid our country is.\"

\"People just pour into the country. (Americans are) disgusted when a woman who\'s nine months pregnant walks into the country and has a baby and you have to take care of that baby for the next 85 years.\"

\"They\'re never going to do anything with these countries. It\'s an instinct - they don\'t have it. It\'s just going to be more of the same.\"

Taking on the Republican frontrunner on the immigration issue, Biden Tuesday accused Trump - naming him twice - as reverting to \"xenophobia\" in a play for votes.

\"There\'s one guy absolutely denigrating an entire group of people, appealing to the baser side of human nature, working on this notion of xenophobia in a way that hasn\'t occurred in a long time,\" he said at a reception marking Hispanic Heritage Month.

Biden also called Trump as the purveyor of a \"sick message\" about immigrants coming to the US. He said that political tack wouldn\'t ultimately resonate with most of the country.

More Republicans see Trump as their best bet: Poll