A closely watched matchup is set between U.S. Sen. Ted Cruz and his Democratic challenger, U.S. Rep. Beto O'Rourke.
Cruz and O'Rourke clinched their parties' nominations Tuesday. O'Rourke has raised more money than Cruz so far.
Gov. Greg Abbott also clinched the Republican nomination for governor and enters the general election as a heavy favorite against whoever emerges from the Democratic primary.
Polling places in El Paso and far West Texas closed at 8 p.m. CST, an hour later than the rest of the state.
A Democrat has not won a statewide race in Texas since 1994.