Vermont Sen. Bernie Sanders is urging party unity in his first visit to Wisconsin since defeating Hillary Clinton in the state's Democratic presidential primary.

Sanders also delivered harsh words for Republican presidential nominee Donald Trump, saying Wednesday that bigotry is the cornerstone of his campaign. Sanders said, "We are not going to allow Donald Trump to divide us up."

Sanders spoke to about 1,200 people at a rally in Madison. He was joined by Democratic U.S. Senate candidate Russ Feingold, who tailored his message to young people.

Feingold said a Trump presidency would allow "right-wingers" to control the Supreme Court for a generation.

Sanders is also making a pitch to young voters, touting Clinton's support for free college tuition for middle income families and lowering of college debt.