(CNN) A moderate Democrat with a record of winning in Tennessee will face off against a firebrand conservative in November, in a contest for US Senate that is remarkably competitive for the Republican-leaning state.

Democratic former Tennessee Gov. Phil Bredesen and Republican Rep. Marsha Blackburn won their respective primaries, CNN projects. Their victories were widely expected.

The race to be the Volunteer State's next governor also came into focus on Thursday, where attention in recent weeks has been on the competitive and nasty fight for the Republican nomination among Rep. Diane Black and businessmen Bill Lee and Randy Boyd.

Lee will win the GOP nomination, CNN projects, defeating Black, who was backed by Vice President Mike Pence.

The Senate race is slated to be one of the most hotly contested of the 2018 midterms. Republicans had never expected to be competing for a Senate seat in ruby-red Tennessee, but Bredesen's cross-party appeal and Trump's sagging popularity have made the race competitive. CNN currently rates the race as Lean Republican.

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