Texas Attorney General Ken Paxton leads Senator John Cornyn in polling for their Republican Senate primary runoff, according to a new Change Research poll showing Paxton with 42 percent support among likely Texas Republican primary voters.

The two Republicans advanced to a runoff election after neither candidate secured a majority in the initial primary contest. Both candidates are now actively courting President Trump's endorsement, which could prove decisive in the race.

Trump indicated days after the runoff was set that he planned to endorse one candidate and ask the other to withdraw from the race. However, the formal dropout deadline passed Tuesday without Trump making an endorsement or either candidate exiting the contest.

Cornyn, who has served in the Senate since 2002, faces a challenge from Paxton, who has been Texas Attorney General since 2015. The runoff represents a significant test for the incumbent senator against a Trump-aligned challenger.

The polling suggests Trump's endorsement could be crucial for Cornyn's chances of retaining his seat. The race reflects broader dynamics within the Republican Party as Trump-backed candidates challenge establishment figures in primary contests across the country.

The runoff election will determine which Republican advances to the general election for the Texas Senate seat.