What are the chances of an contested 2020 Democratic convention?

[NewYorkExpress]

If Sanders is running again, I'd say it's likely, because I doubt he drops out before the convention, even if someone else actually has enough delegates to clinch the nomination.

If it's between two other candidates, it's not as likely, though still plausible if it's between a progressive and a moderate, especially if the progressive has Sanders's endorsement.