Tennessee is the only state in the country to have a Thursday downballot primary. That day of the week is specified in the state's original constitution and has never been modified.  

All polls close at 8:00 PM Eastern Time.  

All Tennessee Results >>

Senate: Republican Lamar Alexander is retiring.  In this deep red state, the primary winner will be an overwhelming favorite in November. As a result, the contest has drawn a large field of 15 hoping to succeed the three-term Senator. The two who have received the most attention are Bill Hagerty, a businessman and former Ambassador to Japan and orthopedic surgeon Manny Sethi.

President Trump has endorsed Hagerty, although both candidates have been trying to prove they are the most Trumpian. The last three polls of the race, including this one from JMC Analytics, have been within the margin of error, although Hagerty has had a small lead in each.

The Democratic frontrunner appears to be James Mackler, an attorney and Army veteran. 

House: The state's nine districts are split between seven Republicans and two Democrats. There's very little to see here in November: none of these seats were decided by less than 29% in 2018. Six-term incumbent Phil Roe (R) is retiring in District 1. Roe won his last term by 56 points, so the primary winner will almost certainly be the district's next representative. A large field is vying to succeed him.

All other incumbents are seeking another term.  A few of them have drawn primary challenges, but none appear to be in jeopardy. You can see all the results here.