Conor Lamb is accusing rival John Fetterman in Pennsylvania’s Democratic U.S. Senate primary of skipping candidate forums to avoid talking about a 2013 incident when shotgun in hand, he confronted a Black man because he suspected the man was involved in gunfire nearby. The accusation marks a sharp escalation in tone between candidates vying for the Democratic nomination for a critical Senate seat in Pennsylvania’s May 17 primary election. The contest to replace retiring Republican Sen. Pat Toomey represents perhaps the Democrats’ best opportunity to pick up a seat in the closely divided Senate. Fetterman’s campaign suggested that Lamb is raising the encounter now because he isn’t breaking through with voters.