The Democratic candidates for Senate in Florida, Ohio and Virginia are leading their Republican challengers, according to the latest Quinnipiac University/New York Times/CBS News polls of likely voters, which complicates efforts by Republicans to win a Senate majority.
Senator Sherrod Brown, Democrat of Ohio, holds an advantage over Josh Mandel, the state treasurer. Mr. Brown was the choice of 51 percent of likely voters to 42 percent for Mr. Mandel. Six percent said they were undecided.
In Virginia, a race between two former governors, Tim Kaine, a Democrat, holds a narrow edge over George Allen, a Republican. Mr. Kaine was the choice of 50 percent to 46 percent for Mr. Allen. Four percent said they were undecided.
In Florida, Senator Bill Nelson, a Democrat, holds a wider lead over Representative Connie Mack, a Republican. Mr. Nelson was the choice of 52 percent to 39 percent for Mr. Mack.
The polls, which were conduc ted Oct. 23 to 28 by landline and cellphone, have a margin of sampling error of plus or minus three percentage points.
Follow Jeff Zeleny on Twitter at @jeffzeleny.
