The first set of Democratic primary debates will take place in Miami over the course of two nights, with 10 candidates appearing on stage together in each debate. But with no precedent for a primary race of 24 candidates, what impact do the primary debates have in influencing voters in a presidential election? Salon's Amanda Marcotte asked professor of political science from the University of Wisconsin-Madison, Kenneth Mayer, on "Salon Talks" how the debates play a role in reshaping the race.

Mayer explained, "There is not a lot of evidence that debates change voters' opinions once we get to the general, but what they typically do is just harden the opinions that people bring to the debate. In primaries they can actually have a somewhat larger effect because the cue of party is absent."

But, Mayer acknowledged how 2020's large number of candidates puts restrictions on how much of an impression they each can make on voters. "Once you subtract the opening and closing statements, we're probably talking about in the range of six or seven minutes per candidate and in a format that is really going to tax viewers' attention," he said.

Mayer predicts that some of the most notable moments in these early debates will be the "zingers, flubs and gaffes." And with most candidates polling below one percent, Mayer notes that the debates "can have a material effect on the size of the field and the relative standing of at least distinguishing between the first tier and the second tier of candidates."

Watch the video above to learn more about how the primary debates can shift the party's eventual nominee. And watch the full episode with Mayer to hear him break down how a front-runner can lose steam and explain how voters can make sense of early polling.