West Hartford - Linda McMahon, a Republican candidate for the U.S. Senate, has hired a former congressional candidate to run her campaign. David Cappiello, a former state senator from Danbury, will begin working as McMahon's campaign manager later this month. Cappiello waged an unsuccessful challenge of Democratic U.S. Rep. Chris Murphy last year. Murphy represents the 5th congressional district. McMahon is one of five Republicans vying for the GOP nomination and the chance to challenge Democratic U.S. Sen. Chris Dodd in 2010.