Donald Trump says he will win Republican nomination even if he loses Wisconsin
Donald Trump says he believes he will still end up with enough delegates to become the Republican presidential nominee even if he loses the Wisconsin primary on Tuesday.
Mr Trump acknowledged in an interview with US broadcaster Fox that last week was not his best of the campaign. He spent much of it on the defence over comments about abortion, Nato and nuclear weapons for Japan and South Korea.
He said it is always better to win and he wants to finish first in Wisconsin.
But the billionaire businessman said that even if he is defeated by rivals Ted Cruz or John Kasich in Wisconsin, "I think I get there anyway" - meaning the party's nomination.
The Republican race is overshadowed by a persistent effort by Mr Trump's rivals in the campaign and the party to force the nomination fight into the July convention.
Wisconsin has emerged as a proving ground for anti-Trump forces as the front-runner's campaign hit a rough patch. Mr Trump defended his campaign manager after he was charged with battery against a reporter, backtracked from comments that women should be punished for having abortions, encountered hostile interviews by conservative Wisconsin talk radio hosts and watched Mr Cruz rise in some preference polls in the state.
Mr Cruz has little chance to overtake Mr Trump in the hunt for delegates who will choose the party's nominee at the national convention. Ohio governor John Kasich has none. Both hope to deny Mr Trump a delegate majority in what is left of the primary season, forcing the nomination to be settled at a contested convention at which one of them might emerge as the nominee.
Amid talk of the Republican establishment trying to block the front-runner, Republican National Committee Chairman Reince Priebus said the nomination process will be clear, open and transparent.
Cameras will be there "at every step of the way" at the convention, he said.
If the race is not settled after all the primary contests, then "we're going to have a multi-ballot convention", with more and more delegates free to pick a candidate of their choice in each round of voting.
But Mr Priebus was clear: "Nothing can get stolen from anyone."
On the Democratic side, the race between Hillary Clinton and Bernie Sanders has grown increasingly bitter, too, though it has not matched the Republican contest for raw hostility.
Their attention will quickly turn from Wisconsin to an even more consequential contest, in New York on April 19, where Mrs Clinton hopes to avoid an upset in the state she served as senator. But Mr Sanders, who was born in Brooklyn, can claim New York as his home state.
Mrs Clinton said she was confident the two campaigns could settle on a debate date before the New York primary.
In recent days, Mrs Clinton has taken issue with Mr Sanders's suggestions that her campaign is being aided by fossil-fuel interests, and in the broadcast interview, she accused Mr Sanders's aides of doing insufficient research about her record of standing up to oil and gas companies.
"We were not lying," Mr Sanders told US broadcaster CNN. ''We were telling the truth."
Among the Republicans, Mr Kasich expressed confidence that Republicans would have an "open convention", but suggested it would not involve the type of unseemly chaos that party leaders fear will play out on national television, dampening their prospects for winning the presidency and possibly House and Senate races, too.
Mr Kasich told ABC television that a contested convention will be "so much fun".
"Kids will spend less time focusing on Bieber and Kardashian and more time focusing on how we elect presidents," he said. "It will be so cool."