Bernie Sanders holds rally at Central High School in Phoenix for Hillary Clinton

Hillary Clinton's onetime rival for the Democratic nomination for president campaigned on her behalf this weekend.

Sanders headlined a rally at Central High School, 4525 N. Central Avenue, on Sunday.

The rally is billed as a way to encourage efforts to increase voter turnout.

The visit is Sanders' second in Arizona as a surrogate for Clinton. Last month, he visited Flagstaff and Tucson to encourage people to participate in early voting.