Thune's endorsement brings Senate leadership one step closer to coalescing around a Republican they spent months trying to defeat.

Paxton faces Democrat James Talarico in the general election.

Texans are choosing a Republican nominee for U.S. Senate.

Cornyn led the March primary with 42% of the vote, narrowly ahead of Paxton’s 40.5%, sending both to a runoff.

Paxton defeated Cornyn with more than 60% of the vote, delivering a major upset against the Senate GOP's long-serving member.