Willie Nelson will perform this Sunday at a campaign event in Austin for Democrat Beto O'Rourke. Nelson has been supporting Democratic candidates since Jimmy Carter in the 1970s. O'Rourke is challenging Republican Gov. Greg Abbott in the November election. Sunday's event is scheduled for 2 p.m. at the Moontower Saloon in South Austin. It'll be a smaller version of a 2018 show where Nelson performed in support of O'Rourke's unsuccessful attempt to unseat Republican U.S. Senator Ted Cruz.