Sanders has long made the case that his economically populist agenda, including his longtime opposition to free trade deals, would enable him to win the industrial Midwest and with it the Electoral College. But Democrats in Michigan, as well as Sanders’ aides and allies, say the race between him and Biden is tight, and a recent poll by Detroit News/WDIV-TV found Biden in the lead by seven percentage points.

“Remember, I’m the one who four years ago this weekend said that to you all I think Bernie Sanders will win my district,” said U.S. Rep. Debbie Dingell, who represents Michigan’s 12th District, which includes Dearborn, home to a large Muslim and Arab-American population. This year, she said, Michigan “is competitive. … I think the senator is going to have to work hard to keep the victory he had four years ago.”

However, Dingell, who attended a Sanders event Saturday but is remaining neutral in the primary, predicted that Sanders will win her district again. “He’s all over my district,” she said.

Michigan is such a critical state for Sanders that he has canceled events in other states, including Mississippi, in order to blanket Michigan with eight events, including rallies, roundtables and town halls in the week leading up to the primary. Several of Sanders’ top aides have also been dispatched here, and Alexandria Ocasio-Cortez was added to the lineup for his rallies in Grand Rapids and the University of Michigan.

The Sanders campaign tacked onto his calendar a rally in Dearborn, which attracted a diverse crowd and a large presence of Arab-Americans. A Shia imam, a Sunni state representative, a Palestinian surrogate and a Yemeni activist all spoke at the event, and an opening act featured dancers wearing Palestinian keffiyehs.