Polls show mixed results, with Paxton and Cornyn in close battle against Democrat James Talarico.

United States President Donald Trump has endorsed Texas State Attorney General Ken Paxton in the Republican run-off to represent the state of Texas in the US Senate in advance of next week’s Republican primary.

In a lengthy post on Truth Social, Donald Trump said that Paxton has been “extremely loyal to me and our AMAZING MAGA MOVEMENT” while also saying that his opponent, incumbent John Cornyn, was not supportive of him when “times were tough”.

In March, Trump said the candidate who did not earn his endorsement should “DROP OUT OF THE RACE”.

In order to clinch the party nomination in Texas, a candidate must win a clear majority. Neither candidate met that threshold in the state’s primary election in early March.

Texas also has open primaries, meaning a voter does not have to be a member of a given political party to vote in that party’s primary. However, voters must pledge to vote only in one party’s primary election.

Paxton has long been the favourite to take the state’s Republican nomination, but faces a tighter race in the general election. Paxton, 63, has never lost an election despite his political career facing waves of controversy, including adultery and facing indictment on felony securities fraud charges. Paxton was also impeached, including by members of his own party.

Recent polls have the Republican run-off as a tight race. An early May poll from Texans for a Conservative Majority, a super PAC aligned with Senator Cornyn, 74, had the incumbent leading by 1 point. Meanwhile, a Lone Star Liberty PAC poll, backed by a pro-Paxton Super PAC, showed the attorney general leading by 11 points.

More independent polls, like one from the University of Houston Hobby School of Public Affairs, showed Paxton with a 3-point advantage.

Texas Republicans have expressed concern about how Paxton would fare in the general election. Matt Shaheen, a Texas state representative, said that “Ken Paxton would be a disaster for Texas conservatives!” in a post on X.

Trouble with the Senate

The Republican nominee will face a tough general election. Polls suggest that James Talarico is either the favourite or within the margin of error. A newly released poll from the Barbara Jordan Public Policy Research and Survey Center found that in a general election matchup, Talarico is tied with Paxton, while Cornyn would lead by 1 point.

Other polls are more stark. A University of Texas poll shows Talarico winning by 7 points in a Cornyn matchup and by 8 points in a Paxton matchup, while Texas Public Opinion Research shows Talarico leading by 5 points against Paxton and 3 against Cornyn.

Democrats have long said that many statewide races could turn Texas Democratic. However, despite those claims, Democrats have not held statewide office in the Lone Star State since 1994.

Strategists believe this endorsement will also hurt Trump’s relationship with the current Senate.

“Paxton, more likely than not, would have won without Trump’s endorsement. Now Trump has alienated the Republican majority in the Senate, Senator Thune, in particular, who’s been lobbying nonstop for Trump to endorse Cornyn,” Mark Jones, professor of political science at Rice University in Houston, Texas, told Al Jazeera.

“He’s also bought himself a John Cornyn who, if he loses on May 26th, has little reason to support the Trump administration during his final seven months in office.”

Republicans currently hold a majority in the US Senate, with 53 seats. Democrats hold 45 seats, along with two independents — Bernie Sanders of Vermont and Angus King of Maine — who caucus with the Democrats.