The Democratic National Convention's rules only state that, "Delegates must, in all good conscience, reflect the sentiments of those who elected them."
With President Joe Biden giving up the nomination, it's basically open season.
The delegates who have pledged to back Harris can change their minds up until the final vote at the DNC in Chicago next month.
In the meantime, other candidates could still come forward. However, experts said they would need support from at least 300 delegates going into the convention. Experts also said defections are unlikely.
Democrats have already planned a virtual roll call before the convention to ensure unity behind Harris. That would create the smoothest path to getting her name on the ballot, but Republicans are working to create speed bumps in the road.
Political reporter Kaleigh Rogers with FiveThirtyEight Politics said, "It's a little fuzzy if it's allowed for Biden's campaign finances to just transfer to Harris' campaign. She was on the ticket with him as the Vice President, but it's a little unclear whether that's okay. It's possible a republican campaign or group may challenge that legally."
Rogers added that it's unlikely Republican challenges will be successful.
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