Who is John Fetterman, the Pennsylvania lieutenant governor running for Senate?

John Fetterman is the Democratic lieutenant governor of Pennsylvania vying to be the state’s U.S. senator.

Fetterman, 52, received national notice during his time as mayor of Braddock, a small Rust Belt town outside Pittsburgh. He ran unsuccessfully for Senate in 2016. But he’s the Democratic front-runner in the May 17 primary, leading his opponents in the polls and in campaign fund-raising by wide margins.

He’s known for an unconventional political style and demeanor, which he’s embraced to connect with more rural voters, who are increasingly disaffected from the Democratic...