US Republican and Democratic Party frontrunners Donald Trump and Hillary Clinton were both beaten in the Wisconsin presidential primary elections last night.
Ted Cruz easily won the Republican primary dealing a blow to Mr Trump's hopes of amassing enough delegates for the party's nomination and boosting chances of a rare contested convention.
Mr Cruz's double-digit win over Mr Trump was a breakthrough for Republican Party forces battling to block the controversial New York billionaire, and it raised the prospect of a prolonged nomination fight that could last to the July convention in Cleveland, Ohio.
Fighting talk.. Ted Cruz targets victories over Donald Trump and Hillary Clinton after his Wisconsin triumphhttps://t.co/pA3u0ey1Lt
— RTÉ News (@rtenews) April 6, 2016
Democratic presidential contender Bernie Sanders also won in Wisconsin, gaining momentum in his fight against Ms Clinton and trimming her commanding lead in delegates.
Mr Trump entered the night with 737 convention delegates to Mr Cruz's 481, leaving him 500 delegates short of the 1,237 needed to become the party's nominee in the 8 November election.
Mr Cruz said the result in Wisconsin showed the party was beginning to rally behind him, but he acknowledged the growing possibility that the fight could go all the way to the convention.
"Either before Cleveland, or at the convention in Cleveland, together we will win a majority of the delegates and together we will beat Hillary Clinton in November," Mr Cruz told cheering supporters in Milwaukee.
"We're winning because we're uniting the Republican Party."
Mr Trump's campaign released a blistering statement saying Mr Cruz had been propped up "by countless millions of dollars of false advertising" from anti-Trump Super Political Action Committees.
"Ted Cruz is worse than a puppet - he is a Trojan horse being used by the party bosses attempting to steal the nomination from Mr Trump," the Trump campaign statement said.
Blog: 'Delegates, superdelegates and selection conventions'
The Wisconsin primary capped a difficult week for Mr Trump, who was forced to backtrack after saying women who have abortions should face punishment if the procedure is outlawed, and who voiced support for his campaign manager after he was charged with misdemeanor assault for grabbing a reporter.
In the Democratic race, the win for Mr Sanders, a senator from Vermont, is his sixth in the last seven contests for the nomination.
Mr Sanders said his message of breaking up big banks, reining in Wall Street and reducing income inequality was bringing new and young voters into the process.
"What we have been seeing throughout this campaign is extraordinary voter turnout in state after state," Sanders said at a rally in Wyoming.
Ms Clinton, who did not appear in public on last night, tweeted her congratulations to Sanders.
"Congrats to @BernieSanders on winning Wisconsin," Ms Clinton said on Twitter. "To all the voters and volunteers who poured your hearts into this campaign: Forward! -H."
Bernie Sanders says momentum is on his side following latest Democrat primary winhttps://t.co/hcuHa5VHoE
— RTÉ News (@rtenews) April 6, 2016
Mr Sanders still faces a difficult task overtaking Clinton as the race moves to New York on 19 April and to five other Eastern states on 26 April.
Heading into yesterday, Mr Clinton led Mr Sanders by 263 pledged delegates in the race for the 2,383 needed to be nominated at the party's July convention in Philadelphia.
She also has a big lead in superdelegates, who are party leaders free to back any candidate.
Mr Sanders needs to win up to two-thirds of the remaining delegates to catch Ms Clinton, who will keep accumulating delegates even when she loses under a Democratic Party system that awards them proportionally in all states.
Mr Sanders needs to rack up big winning margins over Ms Clinton in the remaining states to close the gap.
He has vowed to stay in the race until the convention, and his campaign said superdelegates could begin to shift their support to him if they see he has popular support.
