HOT SPRINGS, Va.—Former Republican National Committee chairman Ed Gillespie is considering a run against Virginia Sen. Mark Warner (D) next year. “It’s a very winnable race,” the powerful GOP insider told POLITICO in a Saturday afternoon interview. Continue Reading Gillespie, who has never sought public office, floated the trial balloon at The Homestead resort, where about 500 activists and party leaders are gathered for a three-day annual meeting known as “The Advance.” (PHOTOS: Senators up for election in 2014) “It’s safe to say that there’s people talking about it here, and I’m listening to them,” he said, noting that nearly...