Willie Nelson is throwing his support behind Democrat Beto O'Rourke in the upcoming mid-term elections in Texas. The country legend is set to headline a rally for O'Rourke in Austin on Sept. 29.

Nelson will headline a concert at a rally for O'Rourke that that is scheduled to take place at Auditorium Shores in Austin, topping off a lineup that includes Lukas Nelson & Promise of the Real, Particle Kid, Carrie Rodriguez, Tameca Jones and Joe Ely. The performance will mark the first time the 85-year-old music icon has ever performed a public concert on behalf of a political candidate, according to a press release. O'Rourke will be on hand to address the crowd at the rally in person.

"My wife Annie and I have met and spoken with Beto and we share his concern for the direction things are headed," Nelson says. "Beto embodies what is special about Texas, an energy and an integrity that is completely genuine."

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O'Rourke is currently serving as a Congressman from El Paso, and he's running for the U.S. Senate seat currently held by Ted Cruz. The charismatic politician is running a grassroots campaign that does not accept money from organized PACs, and he has campaigned energetically, visiting all 254 counties in Texas and conducting town hall meetings, where he meets Texas voters and speaks with them face-to-face. Recent polling has O'Rourke unexpectedly running neck-and-neck with Cruz, and some pundits are predicting he could actually win against the longtime incumbent Republican, according to the New York Times.

O'Rourke made headlines when he appeared onstage with Nelson at the icon's annual 4th of July picnic in 2018, joining Nelson's band onstage to play guitar and sing during the closing medley.

"Amy and I have had the amazing opportunity to talk with Willie and Annie about the kind of future we want for our state when everything we care about is on the line," O'Rourke says. "We are grateful to have Willie's support as we continue running this race the right way: no PACs, no corporations, no special interests — just the people of Texas coming together to do something absolutely incredible."

Registration for the Sept. 29 event is currently open at O'Rourke's campaign website.