The 2018 TN Senatorial Election by State Legislative District - one of the most famous examples of the increasing rigidity of Partisanship - Popular former governor Phil Bredesen ended up carrying 9 SDs and 29 HDs in his 10.79% loss to Marsha Blackburn, to her 24 SDs & 70 HDs.
As mentioned by others, the GOP Firewall in Tennessee is the Unionist Eastern Tennessee, which Bredesen could not overpower due to the Central Tennessee & Western Tennessee Rurals not going below 60% for Backburn due to partisanship,
despite Bredesens historic relative Performance in the Nashville, Memphis, and Knoxville suburbs - along with the smaller cities/suburbs of Tennessee.
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