Former presidential candidate Tim Ryan warned that Democrats could lose 48 states in 2020 if they picked a democratic socialist to lead the ticket.

Ryan, an Ohio congressman who has endorsed Joe Biden since dropping out, argued that picking Bernie Sanders would be a mistake for Democrats. He told Fox News on Tuesday that the public would not support a self-described democratic socialist.

“I, personally, am very, very concerned about some of the folks who are running,” Ryan said. “I think, you know, if we run under a democratic socialist banner in 50 states, I think we lose the industrial Midwest. I think we lose 48 states. I think we lose working-class union voters who have negotiated their private healthcare and want to keep it, and they don’t want to be forced into a public healthcare system.”

He added: “You lose those voters, and I think some of the other issues as well. I think that would be disastrous for us. I think Joe Biden is the absolute best candidate for us. I think he beats Donald Trump in the swing states and the industrial Midwest, and it’s going to be a new day in America.”

Ryan touted Biden’s electability across the country, but the former vice president struggled in Iowa and announced that he wouldn’t stay in New Hampshire to see the results Tuesday night, instead opting to go to South Carolina. Ryan suggested that Iowa and New Hampshire were “road games” and claimed that Biden would start to see some victories when he “plays some home games” in South Carolina and other industrial states on Super Tuesday.

Ryan’s concerns are not unfounded. A Gallup poll released on Tuesday revealed that a majority of respondents would not support a socialist for president.

[Opinion: Bernie Sanders has a socialism problem]