Results of recent U.S. presidential election polls:
In an average of national polls compiled by Real Clear Politics, Democrat Hillary Clinton leads Republican Donald Trump by an average of six points.
In a recent Quinnipiac University poll of likely voters, Clinton leads Trump, 50 percent to 44 percent.
A Bloomberg poll of likely voters finds Clinton leading Trump, 47 percent to 38 percent.
A Reuters/Ipsos poll of likely voters, finds Clinton over Trump, 42 percent to 38 percent.
However, a Rasmussen poll on Wednesday finds the two candidates in a dead-even heat, each drawing 42 percent support among likely U.S. voters.
Millions of people are expected to tune in to watch the third and final U.S. presidential debate Wednesday, being held in Las Vegas and beginning at 9 p.m. EDT (0100 UTC).
Television ratings for the second debate, held October 9, was about 66.5 million people -- sharply down from the 84 million who watched the first debate on September 26.