Bernie Sanders delivered a blistering denunciation of Donald Trump's candidacy at the outset of a raucous rally in San Bernardino on Tuesday night, insisting the billionaire businessman will be doomed this fall. "Donald Trump will not become president of the United States," Sanders said. "The American people are not going to support a candidate who insults Latinos ... who insults Muslims, who insults women." Applause erupted among the roughly 5,000 supporters gathered in an events center here. Sanders, who trails Democratic front-runner Hillary Clinton in the popular vote and the delegate tally, has barnstormed throughout California in the run-up to the June 7 primary. The rally on Tuesday night followed events during the day in Anaheim and Riverside. Sanders has largely avoided overtly criticizing Clinton and focused on Trump, assailing him and Republicans as out of touch with the American people. Still, citing a recent NBC/Wall Street Journal poll that showed him beating Trump in a head-to-head matchup, Sanders insisted that he's the best candidate to defeat the New York real estate mogul. "If the Democratic Party wants a candidate to defeat Trump and defeat him bad, we are that campaign," he said. Noticeably absent from Sanders' hourlong address was the December terrorist attack in San Bernardino in which 14 people were shot to death by a married couple inspired by Islamic State extremists. During debates this spring and on the campaign trail, Clinton asserted that Sanders lacked experience in foreign policy and national security. Sanders' supporters remain committed to his underdog campaign. Among them is Arthur Moore, a 61-year-old retiree. "I'll write his name in if he's not the nominee," Moore said outside the events center before the rally. "I'm done with the Clintons."