"He's made very clear he'll say anything to get publicity and to get elected."
"We want to open up the Democratic Party for new people, new blood, new energy."
Two-thirds of voters said presidential candidates should release their tax returns.
The poll also shows that Clinton leads Trump by 4 points.
The fundraiser was co-hosted by CAA's Bryan Lourd and Vogue editor Anna Wintour.
Trump took to Twitter to defend his work with veterans.
“I think it’s a little bit insulting to the people of California," Sanders said.
"Don’t talk about him as though he’s a regular candidate who’s fit to be president, because he’s not."
Vince Foster committed suicide when he was an aide to former President Bill Clinton.
"We haven't resolved the race issue adequately," Carter said of the United States.