TEXAS -- Republican Sen. Ted Cruz and Democratic challenger Beto O’Rourke are set to square off tonight in their first debate.

It begins at 6 p.m. and will be held at Southern Methodist University in Dallas. The hour-long matchup will focus on domestic policy. Both candidates will stand at podiums before a 240-person audience.

The debate comes as the Cook Political Report changed its rating of the race from "lean Republican" to "toss-up."

Tonight’s debate is the first of three schedule matchups. The other two are scheduled for Sept. 30 in Houston and Oct. 16 in San Antonio.

You can watch a live stream of the debate here. 

Watch Capital Tonight at 7 p.m. for a full recap of the debate with host Karina Kling and analysis from Republican Ted Delisi and Democrat Crystal Kay Perkins.