(CNN) - A new poll indicates that Democratic Gov. Joe Manchin of West Virginia leads his Republican challenger by double digits in the battle over an open Senate held by the Democrats for over half a century.
According to a Marshall University poll released Friday, 48 percent of likely voters in West Virginia support the popular two-term governor, with 38 percent backing businessman John Raese, the GOP nominee, and 12 percent undecided.
Other recent polls suggest a closer contest, including a CNN/Time/Opinion Research Corporation poll released Wednesday that indicated the two candidates were dead even at 44 percent.
The winner of the special election in November will fill out the final two years of the term of Democratic Sen. Robert Byrd, who died earlier this year. Byrd was first elected to the Senate in 1958.
The Marshall University poll was conducted by West Virginia based Orion Strategies on Monday and Tuesday, with 450 likely voters questioned by telephone. The survey's sampling error is plus or minus 4.6 percent points.
Orion Strategies is public relations, political consulting and advertising business founded and owned by Curtis Wilkerson, who has assisted Democratic candidates. Wilkerson tells CNN that while he does assist Democratic candidates, he says his organization's polls conducted for West Virginia universities, colleges, and media outlets are non partisan.
The poll was conducted as former President Bill Clinton teamed up with Manchin at a rally in Morgantown, and as a new commercial by Manchin's campaign in which the governor says he will "take dead aim at the Cap and Trade bill" before firing a rifle at what appears to be a copy of the Democratic-backed legislation on clean energy and climate change reform, which is unpopular in West Virginia.
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