Milwaukee: Front-runners Donald Trump and Hillary Clinton Wednesday suffered a setback as their rivals Ted Cruz and Bernie Sanders snatched victories in the crucial Wisconsin primary, marking a "turning point" in the intense battle for securing their party's presidential nomination.
Cruz, 45, won the Wisconsin Republican primary, boosting his efforts to blunt the 69-year-old real estate tycoon and moving the party closer to a historic contested convention.
Cruz received 48.3 per cent of the votes to 35.1 per cent for Trump. John Kasich of Ohio was a distant third with 14 per cent.
Sanders, 74, won the Democratic primary by receiving 56.5 per cent votes, posting a decisive victory over Clinton who got 43.1 per cent of the votes. It is the Vermont Senator's sixth straight win over Clinton in recent weeks.
For the 68-year-old former Secretary of State, who has a lead of nearly 500 delegates, it is a still a comparatively easy pathway to nomination as compared to Trump, who has a lead of a little over 200 delegates.
Cruz's Wisconsin victory will hand him at least 33 delegates compared to three that will go to Trump. Trump continues to dominate the delegate race, with 740 pledged delegates to 514 for Cruz and 143 for Kasich.
"Tonight is the turning point," a confident Cruz said at his victory rally asserting that it has turned the tide against Trump, who is also facing opposition from top Republican leaders.
"My campaign is going to earn the 1,237 delegates needed, either before Cleveland or at the convention in Cleveland. Together we will beat Hillary Clinton in November," Cruz said.
"Tonight was a bad night for Trump," Cruz said.
After last night's Wisconsin primary results, it would be a bit difficult for Trump to reach the magical figure of 1,237 delegates.
However, Trump campaign exuded confidence that with the primary season entering states like New York that are favourable for him, he was on his way to get the 1,237 delegates.
But Cruz hoped to get the necessary momentum for the rest part of the primary season.
Similarly, Sanders asserted that with having five of the last six primaries, the momentum is on his side.
Clinton and Sanders are chasing their magic number of 2,383 delegates to win the nomination. Clinton currently has 1,743 total delegates while Sanders has 1,056 delegates.
"With our victory tonight in Wisconsin, we have now won seven out of eight of the last caucuses and primaries. We have won almost all of them with overwhelming, landslide numbers," Sanders told his supporters.