Bernie Sanders is working to convince the Democratic Party faithful that he's one of them as he makes his second run for president.
The Vermont senator is promising party officials and voters that he'll back the Democratic nominee no matter who wins the 2020 nomination.
The self-declared democratic socialist has had a substantial impact on the party since his 2016 primary campaign against Hillary Clinton.
Several candidates in the race have endorsed his ideas, including a single-payer health insurance system.
But some Democrats in early nominating states say they're bothered by his refusal to join the party officially and instead remain an independent.
Others worry that his policies will pull Democrats too far to the left to defeat Republicans in a general election.