The evening reception had a host committee of Hollywood luminaries including DreamWorks co-founder Jeffrey Katzenberg, executive and producer Peter Chernin, actor Rob Reiner and Terry Press, the president of CBS Films, according to the event's invitation. It took place at the home of interior designer Michael Smith and James Costos, a former ambassador to Spain under President Barack Obama, the invite shows.

Joe Biden raked in over $700,000 on Wednesday at a Hollywood fundraiser, one of the biggest hauls so far in the former vice president's campaign to take on President Donald Trump in 2020.

The total eclipsed what Biden raised at his 2020 campaign's first fundraising event in Philadelphia at the home of Comcast executive David Cohen, which was estimated to bring in just over $500,000.

More than 300 people showed up at the Hollywood fundraiser, but not all of them cut checks for the maximum individual amount of $2,800. People familiar with the planning told CNBC that it was "opened up to young professionals," including some who gave $500 to get in the door. Many of the donors came from New York, New Jersey, Delaware, Massachusetts, Florida and Tennessee, the people said.

The event's planning and the mix of donor levels shows that Biden is attempting to appeal to a wider array of contributors. Going into his campaign, many top party donors expressed skepticism to Biden about whether he would be able to pull off a successful fundraising operation.

Then, on the first day of his campaign, Biden raised $6.3 million —more than any of his rivals did in their first 24 hours on the trail. Biden announced his candidacy April 25.

Biden, in his remarks to donors Wednesday, vowed to unite the country if he defeats Trump.

"I promise you if we elect a Democrat this time — I predict to you whether it's me or someone else, but I guarantee you if it's me — what's gonna happen is, we're going to see this country come together like it hasn't in a long time," Biden said. "Because people are tired, they're sick and tired of what's happening. Let's lift our heads up. Again, not a joke, remember who the hell we are. And let's go take it back."

Biden's fundraising tour will continue later this month when he travels to Florida for an event reportedly being hosted by attorney John Morgan, who has been a fierce advocate of legalizing marijuana. Biden also plans to head to Nashville.

A spokesperson for the Biden campaign did not return a request for comment.

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