What started out as a goof on a late night talk show has since evolved into a potential windfall for whatever charitable organization GOP nominee Donald Trump names as the beneficiary of his latest pitch to debate-hungry White House hopeful Bernard Sanders.  

During a speech in Bismarck, N.D., Trump again reversed course on the possibility of facing off against the dark horse Democratic candidate. (Starts at 1:18:32 in above video.)  

“If we can raise for, maybe women’s health issues or something, if we can raise $10 or $15 million dollars for charity, which would be a very appropriate amount, I understand the television business very well, I think it would get very high ratings. It should be in a big arena somewhere. And we could have a lot of fun with it,” Trump said.  

Sanders signed on immediately.

I am delighted that @realDonaldTrump has agreed to debate. Let’s do it in the biggest stadium possible.

— Bernie Sanders (@BernieSanders) May 26, 2016

“Let’s do it in the biggest stadium possible,” he proposed on social media.  

Sanders got on board for a two-man debate almost as soon as Trump agreed to participate during an appearance on “Jimmy Kimmel Live!”

That offer evaporated come morning, with the Trump campaign saying early Thursday that Trump was just kidding the night before when he agreed to meet Sanders for a debate.  

The match-up, “wasn’t a serious idea ,” and “wouldn’t be happening,” Trump campaign sources reportedly told CBS News.  

The clarification came amid rising media speculation about what began as a joke on a late-night talk show and quickly became a Twitter meme .  

Comedian Jimmy Kimmel proposed the hypothetical face-off before June 7 primary balloting in California and other states during a taped interview with Trump on  “Jimmy Kimmel Live!” talk show.  

Sanders’ Democratic rival Hillary Clinton had declined an invitation from Sanders, Kimmel mentioned. Would Trump appear in his place?  

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Trump, the presumptive Republican nominee, responded that he would consider it, as long as the proceeds went to charity.  

A Trump/Sanders debate “would have such high ratings,” he said.  

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The Vermont senator immediately took him up on it. “Game on,” he tweeted.

Game on. I look forward to debating Donald Trump in California before the June 7 primary.

— Bernie Sanders (@BernieSanders) May 26, 2016

Sanders’ campaign still hadn’t lost hope Thursday.  

“We are ready to debate Donald Trump.” Sanders campaign manager Jeff Weaver told CNN . “We hope he will not chicken out.”  

Contact Akin at stephanieakin@rollcall.com and follow her on Twitter at @stephanieakin
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