The Latest on campaign 2016 as voters in Wisconsin head to the polls for the state's presidential primary (all times Eastern Daylight Time):

9:44 p.m.

9:32 p.m.

AP has declared Ted Cruz the Republican winner in Wisconsin.

Ted Cruz has won the Republican presidential primary in Wisconsin. The win gives critics of Donald Trump hope that they can stop the GOP front-runner's rise to the party nomination. They are trying to deny him the majority of delegates and force a contested convention in July.

The Texas senator is casting his victory as a sign that he is the only candidate who can stop Trump. He's calling on Republicans to unify behind him and pushing Ohio Gov. John Kasich to drop out of the race.

Polls have closed in the Midwestern battleground of Wisconsin. Democratic candidate Bernie Sanders leads rival Hillary Clinton in early returns.

Meanwhile, Wisconsin is projected to have its highest turnout in a presidential primary since 1980, but that hasn't translated into problems at the polls.

The state elections board projects turnout at 40 percent of eligible voters.

Exit Polls show that Cruz is riding Trump fear; Sanders excitement.

Wisconsin has 42 Republican delegaates up for grabs. The Democrat primary has 96 delegates.