Businessman Tim Burns (R) left the race to challenge Sen. Bob Casey (D-Pa.) today, citing lack of support from state GOP officials. His departure signals Republicans are winnowing their crowded field of candidates ahead of the April 24 primary. Over the past week, Gov. Tom Corbett (R) and the Pennsylvania State Committee endorsed businessman Steve Welch for the GOP nod. Burns suggested in a statement that this effectively ended his statewide campaign. (more…)