U.S. Senator Warner leads in Virginia poll, but Obamacare weighs

U.S. Senator Mark Warner speaks during an interview with Reuters in WashingtonBy Gary Robertson RICHMOND, Virginia (Reuters) – U.S. Senator Mark Warner holds a 15-point lead among Virginia voters over Republican challenger Ed Gillespie, but the Democrat's support for Obamacare could cost him votes in the November election, according to a poll released on Thursday. Warner is favored by 46 percent of voters as he seeks a second term, compared with 31 percent for Gillespie, a former chairman of the Republican National Committee, according to the Quinnipiac University survey. Libertarian Robert Sarvis has 6 percent backing. Warner voted in 2010 for the Affordable Care Act, or President Barack Obama's signature healthcare reform, which has had a troubled launch.