He wants that to make the debate more inclusive than just using polling. The first two debates are slated for June and July. They'll be the first two of six debates in 2019, with at least six more to follow in 2020.

Perez reaffirmed Wednesday that he'd "draw lots" to assign candidates to the two stages rather than separate perceived leaders from a second tier as Republicans did in their large primary field during their 2016 nominating fight.

This story has been corrected to show that Democratic National Committee Chairman Tom Perez did not definitively say that debates would have two stages with a total of 16 spots but rather offered that as a speculative example.