Washington (CNN) For months now, the big story in the 2020 Democratic presidential race has gone something like this: There are just so many of them!

That narrative will begin to change right around midnight Wednesday, when the qualifying window for the third presidential debate closes. At the moment, 10 candidates -- out of the 21 still running -- have met the qualifications (130,000 individual donors, four national or early-voting state polls at 2% support or more) to make the debate stage in Houston on September 12.

Barring some sort of unexpected poll release, which, well, isn't going to happen, the race will split in two starting tomorrow between, broadly speaking, the have-a-chances and the don't-have-a-chances.

Sen. Kirsten Gillibrand was the first to drop , announcing Wednesday night that she was ending her campaign.

The simple fact is that if you are running for president but can't make it onto a debate stage that 10 of your fellow candidates made, it's going to be very, very hard to justify staying in the race all that much longer. How do you go to donors and ask them to give -- or give more -- to a candidacy that is, by the Democratic National Committee's standards, not in the top 10 most viable? And if you can't raise money, how do you pay your staff and run a real campaign?

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