DALLAS (CBSDFW.COM) – Two Texans are among ten Democratic presidential candidates set to face-off this evening in Miami during the first of two nights of debates.

Former El Paso Congressman Beto O’Rourke and former San Antonio Mayor and HUD Secretary Julian Castro will be joined by Massachusetts Senator Elizabeth Warren, the leading candidate in Wednesday night’s lineup and New Jersey Senator Cory Booker, who like O’Rourke is considered part of the top tier.

One key question is with ten candidates, five moderators and a limited amount of time to speak, how can the participants score a win?

The Director of Debate and a Professor at SMU, Dr. Ben Voth, says the candidates need to know which statements they’ve made that have gone over well with Democrats. “What are my five winner, zinger lines and they have to watch debate transpire and when they hear either a questioner or another debater say something that leads into that zinger, then they need to deploy that zinger with some passion and strong eye contact for the camera.”

Democratic presidential candidates in first debate

On Thursday night, ten other candidates take the debate stage in Miami.

They include the frontrunner, former Vice President Joe Biden, Vermont Senator Bernie Sanders, California Senator Kamala Harris, and South Bend, Indiana Mayor Pete Buttigieg along with six others.

Those four are in the top tier.

Democrats wanted to split the candidates randomly, instead of doing it like the Republicans did for the 2016 primary who had a varsity and junior varsity debate line-up.

Professor Voth says he expects the candidates on both nights to take jabs at Biden so they can deflate his poll numbers and pump up theirs, and he says they should.

“I think everybody is going to have a certain incentive to hit Biden because he’s significantly ahead. He’s 15-30 points ahead of the field, so not making some contrast statement with him probably a mistake.”

A Morning Consult-Politico poll shows climate change, gun policy, and recent abortion bills are the three top issues Democrats want discussed at the debates.