WASHINGTON – Two nights. Twenty candidates. Four hours of policy questions. Of course, you're asking, "When can I get more?"

After their meeting in Miami on June 26 and 27, the Democratic candidates for president will square off on a primary debate stage again in Detroit on July 30 and 31.

Like the debate this week, the upcoming one in the swing state of Michigan – which helped propel Donald Trump to the presidency in 2016 – will feature 20 candidates out of the two dozen Democrats campaigning for their party's nomination.

The cut for the debates is determined by polling and fundraising thresholds. The candidates must meet one of two criteria to participate: registering at least 1% support in three polls, or getting donations from 65,000 people (and those have to somewhat spread out, with a minimum of 200 donors in at least 20 states).

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If the four candidates who didn't make the debate in Miami meet those criteria in time for the CNN debate in Detroit, the participants will be determined by polling average. The candidates who had to watch the first debate from the sidelines were Montana Gov. Steve Bullock; Miramar, Florida, Mayor Wayne Messam; Massachusetts Rep. Seth Moulton; and former Pennsylvania Rep. Joe Sestak.

After Detroit, the next Democratic debate won't occur until Sept. 12 and 13. That debate will be hosted by ABC News and Univision at a location still to be announced. The criteria for making the debate stage for that one will be a bit higher: 2% support in at least four polls and 130,000 donors.

Overall, there will be 12 debates in the Democratic primary, including the one that occurred Wednesday and Thursday. Six will be held in 2019, and six more will be in 2020.