Even as she was losing the Wisconsin Democratic primary to Bernie Sanders, Hillary Clinton spent Tuesday evening with top Jewish donors at a fundraiser hosted by Jack Bendheim in Riverdale, NYC, Jewish Insider reported. The next major contest between Clinton and Sanders in the race for the 2016 Democratic party presidential nomination will be on April 19 in New York. Bendheim is president and CEO at Phibro Animal Health Corporation, and served in the past as deputy chairman of AIPAC . In 1999, when Clinton ran for the US Senate in New York, he served as a fundraiser in her campaign and an advisor on Israel. “He is one of few Orthodox Jews to have a close relationship with Clinton,” the Jewish Week wrote at the time . There were 60 participants in the fundraiser, which took place as polling booths closed in Wisconsin. Unsubstantiated reports on the amount raised vary from $60,000 to $600,000. Clinton is leading Sanders by about 700 delegates, including a lead of more than 400 among superdelegates . “ Any gains he would get out of Wisconsin would be temporary and she's probably going to more than make up that ground in two weeks,” said Eric Kasper, a political science professor at the University of Wisconsin-Eau Claire, told Bloomberg news. “If Clinton wins New York, especially if she wins it by a significant margin, it becomes almost impossible for him to get the nomination .” Polls show Clinton leading Sanders by 10 points or more in New York. But Sanders's campaign has begun talking about beating her at the Democratic convention by wooing superdelegates, who, unlike pledged delegates, have the freedom to switch allegiances . Sanders's campaign manager, Jeff Weaver, told CNN Tuesday that he expected neither Clinton nor Sanders would secure the 2,383 delegates needed to clinch the nomination before the convention. He said Sanders could overtake Clinton then with the help of the superdelegates. The Clinton campaign on Tuesday night said in an e-mail to supporters that Weaver's suggestion of an open convention and flipping delegates would amount to “overturning the will of the voters .” “Your vote is your voice, and the Sanders campaign shouldn't be trying to circumvent the process,” the e-mail said.