Marsha Blackburn vs Phil Bredesen.

The first U.S. Senate debate between Democratic ex-Gov. Phil Bredesen and Republican Congresswoman Marsha Blackburn is set for Sept. 25.

Blackburn’s campaign announced Monday she’ll join the Cumberland University debate in Lebanon, adding that they are “looking forward to this debate and others.” Hosts include The Tennessean, the League of Women Voters of Tennessee, WTVF-TV and WNPT-TV.

Bredesen previously agreed to participate in that debate and three in Memphis, Chattanooga and Knoxville.

Blackburn campaign spokeswoman Abbi Sigler says the Sept. 13 Memphis debate at Rhodes College doesn’t fit their schedule.

Bredesen said he’ll host his own forum there because the closest debate to Memphis shouldn’t be 200-plus miles away.

The race to replace retiring Republican Sen. Bob Corker could be pivotal for the slim Republican Senate majority.