HARRISBURG, Pa. (AP) – The leading candidates for the Democratic nomination for Pennsylvania’s open U.S. Senate seat held their first live-televised prime-time debate. John Fetterman is the state’s lieutenant governor, and has led polls and fundraising. He took the brunt of the attacks from state Rep. Malcolm Kenyatta of Philadelphia and U.S. Rep. Conor Lamb of suburban Pittsburgh. Perhaps the sharpest exchange in Thursday night’s debate centered on a 2013 incident when, shotgun in hand, Fetterman confronted someone he believed was involved with gunfire on a nearby street in Braddock, where Fetterman was mayor. The debate also exposed differences over suspending the federal gas tax and opposing new natural gas drilling leases.