The Democratic National Committee said Thursday it will delay its presidential nominating convention in Milwaukee by a month, to August 17. The DNC’s announcement came as Democratic front-runner Joe Biden urged Wisconsin to proceed with in-person voting at polling sites across the state during a scheduled primary election next Tuesday.

Joe Biden: “A convention having tens of thousands of people in one arena is very different than having people walk into a polling booth with accurate spacing to six to 10 feet apart, one at a time going in, and having machines scrubbed down.”

On Thursday, a federal judge declined to postpone the election but said Wisconsin was ignoring public health data and “endangering its population.” Wisconsin’s poll workers are overwhelmingly elderly, and many have health conditions that put them at high risk of death if they’re infected. Democratic Governor Tony Evers has called up the National Guard to fill in for an estimated 7,000 poll workers who’ve refused to participate.

Biden’s opponent, Senator Bernie Sanders, has called for a delay to allow Wisconsinites to vote entirely by mail. Wisconsin Senator Tammy Baldwin and the mayors of Milwaukee, Green Bay and Racine are also calling for a delay.

Wisconsin has reported at least 38 deaths from COVID-19, and residents who wish to brave in-person voting will be exempted from a shelter-in-place order.