Sen. Marsha Blackburn (R-TN) is her state's governor-elect. She can choose her replacement to finish her term in the Senate. A couple of solid names are being tossed around, including Rep. Tim Burchett. He has a shot. It’s up to her, but Sen. John Thune (R-SD) is reportedly not pleased with the selection, so much that he might be working to block the appointment (via Just the News):

Rep. Tim Burchett, R-Tenn., is reportedly eyeing Sen. Marsha Blackburn's, R-Tenn., seat in the upper chamber and is excited that Senate Majority Leader John Thune reportedly opposes him for the post.

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"I think I've got a good shot at it, I think it's totally up to her," Burchett said on Fox News.

In a separate interview with radio host Todd Starnes, Burchett said he had been told that Thune was working to keep him from receiving the appointment. 

"I had an off-the-record conversation with a fairly prominent member of the media that said Thune had sent the word out that he does not want me because I would not be - I would not do - what leadership told me to do type thing," Burchett said. "And I said, you know what, you're exactly right."

Thune doesn’t like it — that’s good enough for me. We’ll need fighters in the Senate for the next two years, and Burchett fits the mold. Mr. Thune certainly doesn't have those qualities.