A "stripped down" version of the rock band Wilco will perform a free concert at Union Theater as part of Campaign for Change, a Barack Obama rally featuring speakers U.S. Sen. Russ Feingold and U.S. Rep. Tammy Baldwin on Saturday afternoon.

Three of Wilco's six members — frontman Jeff Tweedy, bassist John Stirratt and multi-instrumentalist Pat Sansone — will perform at the event, which begins at noon, according to Wilco publicist Deb Bernardini.

Free tickets will be distributed on Wednesday at Campaign for Change's student office, 216 N. Henry St. and at the Wednesday farmers' market on Martin Luther King Boulevard. The Union Theater's capacity is 1,300.

Wilco's last show in Madison in September 2007 at the 2,200-seat Overture Hall sold out in one day.

Doors will open in Union Theater, 800 Langdon St., at 11 a.m. Saturday. After the concert, Baldwin will lead a march to the polls for voters to cast early votes before polls close at 3 p.m.