Republican U.S. Senate nominee Bob Corker has pulled ahead of Harold Ford Jr. in one of the races that could determine whether the Democratic Party takes control of the Senate, according to a poll released Tuesday.

The survey of 541 likely voters found Corker favored by 52 percent, compared with 44 percent for Ford. The cable news network poll was conducted Thursday through Sunday by Opinion Research Corp. The margin of sampling error was plus or minus 4 percentage points.

If Ford wins, he would become the first black senator elected in the South since Reconstruction and the first black candidate elected in a major statewide race in the South since Virginia's Douglas Wilder was elected governor in 1990.

Corker, a former Chattanooga mayor, and Ford, a five-term congressman, are competing for the seat being vacated by Senate Majority Leader Bill Frist. Frist is retiring at the end of the year.

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When registered voters overall — likely to vote or not — were asked about the race, Corker had the support of 47 percent to 45 percent for Ford. The margin of error in the larger sample of 1,015 registered voters was 3 percentage points.

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In the Tennessee governor's race, the CNN poll found Gov. Phil Bredesen with a commanding lead over GOP candidate Jim Bryson, a state senator. Bredesen was favored by 59 percent of likely voters in the poll, compared with 37 percent for Bryson.

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