Democratic front-runner Hillary Clinton and Vermont Sen. Bernie Sanders staked their ground Wednesday night in Florida as both vowing not to deport children and illegal immigrants with a clean criminal record.

Their comments set up a showdown with Republican candidates Donald Trump and Texas Sen. Ted Cruz, who both have vowed to clamp down on illegal immigrants in the country.

Trump and Cruz, along with Florida Sen. Marco Rubio and Ohio Gov. John Kasich will get their opportunity to address the thorny topic Thursday when they debate in the Sunshine State.

Clinton and Sanders squared off in their eighth debate Wednesday night held at Miami Dade College in Florida. The Univision/CNN debate is the final one scheduled this month between the candidates in the running for the 2016 Democratic nomination.  

During the debate, both Clinton and Sanders vowed to push for immigration reform if elected president. 

“The essence of what we are trying to do is to unite families, not to divide families,” Sanders said. 

Clinton says she will extend President Obama’s executive orders shielding some illegal immigrants from deportation.

Clinton called the New York businessman “un-American” and said he traffics in “prejudice and paranoia.”

 “You don’t make America great again by getting rid of everything that made America great,” Clinton said, referencing Trump’s campaign slogan.

Sanders said voters would “never elect” a candidate like Trump. 

Clinton also slammed Trump’s plan to build a wall at the U.S.-Mexico border.

“As I understand, he’s talking about a tall wall. A beautiful, tall wall,” Clinton said, adding that Trump’s plan to keep out immigrants and his claim he’ll get Mexico to pay for it is “a fantasy.” 

Clinton then turned her sights on Sanders, accusing him of supporting legislation that would have led to indefinite detention of people facing deportation, and for standing with Minutemen vigilantes. 

Sanders refuted the notion, which he called "ridiculous" and "absurd," and accused Clinton of picking small pieces out of big legislative packages to distort his voting record.

"No, I do not support vigilantes and that is a horrific statement and an unfair statement to make," he said, adding: "I will match my record against yours any day of the week."

Clinton also dodged early debate questions about ongoing investigations into her use of a private email server when she was secretary of state. When debate moderator Jorge Ramos of Univision asked her if she would drop out of the race if indicted over the handling of her email while secretary of state she replied,"Oh for goodness sake, that is not going to happen. I'm not even answering that question."

The FBI is investigation the possibility of mishandling of sensitive information that passed through Clinton's private email server.

Sanders, as he has in the past, declined to bite on the issue, saying, "The process will take its course." He said he'd rather talk about the issues of wealth and income inequality.

Clinton also defended her role in the deadly 2012 attack on the American mission in Benghazi, Libya.

She said Wednesday that her shifting explanations for the crisis in the early hours were because of changing dynamics and new information. 

Clinton also said the investigation has been politicized by Republicans seeking to score points against her campaign.

"This was fog of war," she said, saying that she regrets the lives lost in the crisis.

She added: "I wish there could be an easy answer at the time but we learned a lot."

Sanders came into Wednesday night’s debate after a surprise primary win in Michigan Tuesday, where he had been trailing by more than 20 points in the polls.

Clinton vowed to keep fighting Wednesday, saying, “It was a very close race. I’ve won some and I’ve lost some.”

Sanders campaign officials made the case Tuesday night that the Vermont senator’s attacks on Clinton’s support for free trade deals had an impact in the Michigan race, and likely will be effective in upcoming contests in Ohio, Illinois and Missouri. 

The Sanders camp maintains Clinton’s advantage in the South will go away after next Tuesday, as rural voters in other states take a closer look at their candidate.

Clinton, though she maintains a healthy lead overall, needs Florida’s 99 delegates up for grabs March 15 to help clinch the nomination. 

The Associated Press contributed to this report.