Conservative fans expressed anger that the musician will headline a free outdoor show in Austin, Texas, in support of the Democrat

This article is more than 2 years old

This article is more than 2 years old

Country music legend Willie Nelson has enraged some of his most conservative fans by announcing plans to play at a huge rally on behalf of Beto O’Rourke, the Democratic insurgent threatening an election upset in Texas.

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The 85-year-old star will headline a free outdoor show in Austin, Texas, in support of the Democrat who is pushing to unseat the Republican senator Ted Cruz in November’s midterms.

“My wife Annie and I have met and spoken with Beto and we share his concern for the direction things are headed,” Nelson said in a press release announcing the event, which his publicist suggested was his first-ever rally on behalf of a politician.

“Beto embodies what is special about Texas, an energy and an integrity that is completely genuine.”

The move seems to have surprised and upset some of Nelson’s fans – even though he has a long record as an activist on a range of liberal issues.

One Texan wrote on Twitter: “Someone buy my Willie Nelson ticket for Friday, November 16. I am no longer willing to watch that hippie guitarist who supports that damn socialist running for Senate.”

A woman wrote on Nelson’s Facebook page: “Just cause you can write a song, sing a song, play a guitar and smoke weed – doesn’t mean you know what’s right for this state!!! Entertainers should stay out of politics & stick to entertaining.”

Another disgruntled fan said: “You should stay out of politics. I’m a lifelong fan this is not a smart move.”

That fan was quickly shot down by a Nelson supporter, who replied: “Lifelong fan unaware of Willie’s decades of political activism.”

From campaigning to legalize marijuana to supporting the LGBT movement, Nelson has scarcely hidden his progressive credentials during his long career.

As well as being co-chair of the National Organization for the Reform of Marijuana Laws, Nelson was a critic of the Iraq war, an advocate of biofuels and a supporter of animal rights campaigns.

Peter Blackstock (@Blackstock360) So @BetoORourke not only stuck around to sing with @WillieNelson, he played guitar with him. pic.twitter.com/HZdod0WLqr

O’Rourke, who was once a member of a punk rock band, joined Nelson on stage at the singer’s Fourth of July picnic, playing guitar and singing harmony on songs including Roll Me Up and Smoke Me When I Die.

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O’Rourke has been accused by Cruz of running from the “hard, hard left like Bernie Sanders”. But Cruz, who was the last man standing against Donald Trump in the 2016 race for the Republican presidential nomination, is feeling the heat. A rash of summer headlines have asked whether he is facing an upset defeat. Latest polling suggests his lead is down to 3.2%.

Last week the New York Times reported that Trump’s budget chief, Mick Mulvaney, had told donors Cruz could lose because he is not “likable” enough.

More than 20,000 people have already signed up for Nelson’s outdoor show in support of O’Rourke, which will be staged at Austin’s Auditorium Shores on 29 September.