Harry Styles, Willie Nelson back Beto for Texas governor. How could that affect the election?

AUSTIN (KXAN) — Harry Styles is riding the "watermelon sugar high" of Beto O'Rourke's gubernatorial campaign, endorsing the Democratic challenger during his fifth performance at the Moody Center Sunday. O'Rourke made a surprise appearance during the concert, appearing on the jumbo screen in the pit.

It was the second of two celebrity endorsements Sunday, coming just hours after Willie Nelson joined O'Rourke for a "Vote 'Em Out" campaign rally and political endorsement. But what's the weight of these endorsements at this stage in the election?

"Celebrity endorsements work best when they're done early and a lot of people haven't made up their minds," said Brian Smith, a political science professor at St. Edward's University. "Because when we see candidates without a lot of name recognition, having a celebrity or somebody famous come out and endorse that candidate will give them instant credibility."

When it comes to Nelson's endorsement, Smith said his wasn't surprising given his history of backing Democratic and progressive candidates. He's also a familiar name in O'Rourke's camp, having endorsed the former U.S. House of Representatives member in his bid for the U.S. Senate against Republican Sen. Ted Cruz in 2018.

"The endorsement of Willie Nelson, although great for the campaign, isn't really going to move the needle because it's just going to reinforce what O'Rourke supporters knew all along: that Willie Nelson, somebody with very progressive credentials, endorsed the candidate who's the most progressive candidate in the race."

With Styles' endorsement, this gets more interesting, given his lack of American citizenship and much younger audience, Smith said. Some of Styles' core fanbase might be under the age of 18 and ineligible to vote.

Those who are fans of Styles are likely already familiar with some of his politics, which have been on display throughout his Austin residency at the Moody Center. For his Love On Tour, Styles has partnered with the nonprofit Everytown for Gun Safety, which advocates for gun control in an effort to reduce gun violence.

Styles has also vocalized his support for abortion access at his Austin shows, telling concertgoers they have the right to make decisions regarding their own bodies.

"I know that there are hard things out there at the moment, and I would like to remind you to take a look around this room," Styles said. "You are not alone at any point. Do not let anyone tell you what you can and cannot do with your body."

Styles' endorsement has already been criticized by the Republican National Committee, with RNC spokesperson Macarena Martinez saying in a statement: "Beto has shown Texans that his priority is cozying up to coastal elites and celebrities. We’ll see in a few short weeks how many are left standing around him when he loses for the third time in November."

Smith added celebrity endorsements, particularly at this stage of an election cycle, don't pack the same weight as a political endorsement would — particularly one where a politician might go against their party to endorse a candidate.

"If a politician comes out and endorses another politician, they're putting their own electoral future in jeopardy," Smith said. "They're going to be very reasoned with that endorsement. So people are also going to look and say, 'I trust that politician. I voted for them in the past. And if they support that candidate, then maybe I will.'"

Within Styles' Love on Tour, he's also been promoting voter registration and displaying QR codes on concert jumbo screens for fans to check out if they're registered to vote.

While registering to vote is a critical first step to civic engagement, voter registration doesn't automatically translate to increased voter turnout.

"Voting itself here in Texas, in particular, means going to the polls, either early or on Election Day, and we haven't been able to bridge that gap yet," Smith said, adding, "a lot of people who are registered to vote still don't vote, and that's what politicians need to do if they're going to win, it's 'okay, you're registered. Now how do I get you out to vote?'"

Texas' voter registration deadline is Tuesday, Oct. 11. The Texas Secretary of State's My Voter Portal allows Texans to check if they're registered to vote, along with viewing their polling and early voting locations along with key election dates.