Supporters of Mike Levin, Democratic U.S. Representative candidate from California, not pictured, cheer during a campaign rally with former U.S. President Barack Obama, not pictured, in Anaheim, California, U.S., on Saturday, Sept. 8, 2018. Obama will begin an aggressive challenge to Donald Trump and his party's grip on statehouses and Congress, an unusual example of a former president openly working against his successor. Photographer: Patrick T. Fallon/Bloomberg via Getty Images
