Tennessee state Rep. Gloria Johnson announced Tue. her bid for the U.S. Senate, setting up a 2024 showdown in the state.

Johnson made headlines this year after she joined two legislators in protesting gun violence on the state House floor.

The trio, known as the "Tennessee Three," organized the protest in wake of a deadly school shooting in Nashville. (AP)

State Republicans moved to expel the trio for "bringing disorder" to the House; only Johnson survived the vote. (AP)

Johnson announced her 2024 Senate campaign outside of a high school she previously worked at as a teacher.

Johnson: "We have got to do something, and well, this is the something I decided to do."

Johnson will face activist and former 2020 Senate candidate Marquita Bradshaw in the Democratic primary. (AP)

Bradshaw lost to incumbent Republican Sen. Bill Hagerty in 2020 by 27 points. (NYT)

Who is up for reelection in 2024? Whoever wins the primary will face incumbent GOP Sen. Marsha Blackburn in 2024.

Blackburn was first elected to the Senate in 2018, defeating Democratic former Gov. Phil Bredesen by 10.8 points.

Democrats have an uphill battle in 2024: the state hasn't elected a Democrat to statewide office since 2006. (WBIR)

Who is Johnson? Johnson was first elected to the state House in 2012; she lost reelection in 2014 and 2016. (AP)

Johnson made a comeback in 2018, winning reelection by 10+ points; she also won reelection in 2020 by 5+ points. (BP)

Johnson: "Tennesseans are fed up with corrupt, ‘do nothing’ politicians, like Marsha Blackburn."

Johnson: "Tennessee women deserve a Senator who trusts them to make their own medical decisions."