The Hillary Clinton campaign emailed Clooney's letter to supporters on Monday, in which he called for voters to rally behind the Democratic presidential hopeful and her "voice of tolerance and experience." The actor-activist and his wife, Amal, a human-rights lawyer, are hosting a fundraiser for Clinton at their Los Angeles home next month.
The Oscar-winning producer didn't actually use Trump's name in the letter but referenced the billionaire's inflammatory campaign rhetoric and slogan.
"If you listen to the loudest voices out there today, you'd think we're a country that hates Mexicans, hates Muslims and thinks that committing war crimes is the best way to make America great again," he wrote. "The truth is that the only thing that would prevent America from being great would be to empower these voices."
Clooney's words come on the heels of him dubbing Trump an "opportunist" and a "xenophobic fascist" in an interview with the Guardian earlier this month.
"In all of this clutter, there's been one consistent voice — a voice of tolerance and experience from a candidate who's spent a lifetime fighting for the rights of the less fortunate. A candidate who knows firsthand the complexity of our international relationships. That candidate is Hillary Clinton," he continued in the letter.
The Oscar-winning producer went on to bolster the former secretary of State as the "only grown-up in the room" if she garnered "an insurmountable delegate lead" and Democratic nomination in the primary process.
The April 16 event — hosted at the actor's Los Angeles home with director Steven Spielberg and Kate Capshaw, studio exec Jeffrey Katzenberg, Haim and Cheryl Saban — is expected to be a major moneymaker for Clinton, with tickets going for $33,400 a a pop, according to CNN. The Clinton campaign hit a major milestone last week by achieving 1 million donors, with the majority giving $100 or less.
Clooney and the Clinton campaign are also holding a contest for supporters to meet the actor, his wife and the former First Lady during the event.
"The good news is," Clooney said, "I'm not cooking."
The "Hail, Caesar!" star also stumped on behalf of President Barack Obama and hosted a fundraiser for the incumbent back in 2012 when Obama was running for reelection. They raised a record-breaking $15 million at that event.
Clooney isn't the first celebrity to lend his voice to the Clinton campaign in the past few days: "Girls" star Lena Dunham and Golden Globe winner America Ferrera showed their support for the Democrat at an event in Hollywood on Sunday.
Meanwhile, "Charles in Charge" alum Scott Baio endorsed Trump during a Saturday appearance on Fox News.
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