Washington (CNN) The Democratic National Committee will double the qualifying thresholds and require that 2020 candidates meet both in order to participate in the third and fourth primary debates, the committee announced Wednesday.

Candidates had to achieve 1% in three polls from an approved list of pollsters or receive campaign contributions from 65,000 unique donors, including 200 donors each from 20 different states, to qualify for the first Democratic primary debates in June, which will be hosted by NBC News, and the second set of debates in July, which will be hosted by CNN.

In order to qualify for the third and fourth set of debates in September and October respectively, candidates will now have to achieve 2% in four polls from a slightly changed list of approved pollsters and receive 130,000 unique donors (from the date of their campaign's creation), including 400 unique donors per state in at least 20 US states.

The doubling of the threshold will mean that a number of candidates who qualified for the first set of debates will no longer meet the qualifications for the debates in September and October, and will now have to work to make up the differences over the next few months.

But the biggest change will be that candidates now have to meet both the polling and donor threshold, not just one like in the first two debates. This is a significant shift that will likely reduce the number of candidates qualified for the third and fourth set of debates.

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