HARRISBURG — Pennsylvania’s larger-than-life lieutenant governor, the 6-foot-8, bald and tattooed John Fetterman, will run for U.S. Senate, making the announcement Monday after kicking off an exploratory fundraising campaign last month that raised over $1 million.

It will be the second bid for U.S. Senate by the plainspoken 51-year-old Democrat. He may ultimately see competition from a member of Congress for his party’s nomination in what could become the nation’s most competitive Senate race in 2022.

Meanwhile, on the Republican side, a number of names are circulating — including former Trump administration figures. Another possibility is Jeff Bartos, a suburban Philadelphia real estate investor who started running for U.S. Senate before switching horses to become Fetterman’s opponent for lieutenant governor in 2018.

The Senate seat in the presidential battleground is being left open after two-term Republican U.S. Sen. Pat Toomey announced in October that he would not run again.

Fetterman is by far the highest-profile name in Pennsylvania politics to show interest in running. He got his start in elective office in 2006 as the mayor of Braddock.