From The Hill, with this on the impact of the pre-convention “virtual roll call,” originally planned in response to the Ohio ballot access problem:

Typically, the Democratic presidential candidate is officially selected at the Democratic National Convention, but this year’s presidential nominating process is set to look a little different. 

Democrats are holding a virtual roll call in response to earlier concerns that the president wouldn’t be able to get his name on the November ballot in Ohio ahead of the state’s filing deadline. In Ohio, Democrats initially needed to submit the name of their candidate to the state 90 days before the election, which is Aug. 7 this year. That’s earlier than when the convention begins: Aug. 19. …

When Ohio Republican lawmakers initially deadlocked over a legislative solution, Democrats decided to instead hold a virtual roll call. Ohio lawmakers later passed legislation after the party came up with their workaround solution, allowing Democrats to submit their candidate to the state by Sept. 1.

More on this topic from New York Magazine: “in order to meet Ohio’s general election ballot deadline of August 7, the Democratic National Committee has voted to hold a “virtual roll call” before the convention (the exact date has not yet been set, though July 21 has been floated as a possibility, raising suspicions the DNC may be trying to run out the clock on any Plan B scenario).”