Donald Trump has one more chance to attack Hillary Clinton in person and try to make up some ground in the polls in the final presidential debate Wednesday night. Clinton, on the other hand, is expected to play it safe and protect her lead. But much will depend on what questions the candidates are asked. 

While only moderator Chris Wallace knows the exact questions Clinton and Trump will have to answer, the general topics for the final debate are public knowledge. The debate will consist of six sections: debt and entitlements, immigration, the economy, the Supreme Court, foreign affairs, and fitness to be president, according to the Commission on Presidential Debates, the independent organization that organizes the debates.

Wallace is expected to spend about 15 minutes on each topic. The questions will highlight some of the candidates' major policy differences. Regarding immigration, Trump has claimed he will build a wall on the U.S.-Mexico border to curb illegal immigration and deport nearly 11 million undocumented immigrants. Conversely, Clinton has laid out a plan that would extend government benefits to non-criminal immigrants and offer a path towards legality or citizenship.

On the debt, Trump has vowed to cut taxes across the board while cutting wasteful government spending. Clinton has promised to raise taxes on the wealthiest Americans. Recent allegations of sexual assault against Trump and Clinton's ongoing email scandal will almost certainly play a role in the discussion about fitness to be president. 

Chris Wallace Fox News anchor Chris Wallace will ask Hillary Clinton and Donald Trump about immigration and the economy in Wednesday night's presidential debate. Photo: Getty Images

A bonus topic of sorts is expected to show up, as well. Many pundits predict Wallace will ask Trump about his recent suggestions on the campaign trail that the November election will be rigged against him. Trump has alleged that the mainstream media is biased against him and that high numbers of voter fraud could turn the tide in key swing states.

"Voter fraud is all too common, and then they criticize us for saying that," Trump said at a rally Tuesday in Colorado. "Take a look at Philadelphia, what’s been going on, take a look at Chicago, take a look at St. Louis. Take a look at some of these cities, where you see things happening that are horrendous."

There is little evidence to support Trump's claims of significant voter fraud. 

Wallace will be tasked with holding the candidates' feet to the fire while discussing these topics. The three-time Emmy Award-winning journalist is the host of "Fox News Sunday." In 2006, the Washington Post revealed that the 69-year-old is registered as a Democrat but he claims this is only to qualify for primary voting in Washington, D.C. Trump has criticized the previous debate moderator for showing bias against him, but Trump campaign representatives have said they expect Wallace, who works for the generally right-leaning Fox News, to be fair. 

The 90-minute debate will be held at the University of Nevada in Las Vegas. It is slated to begin at 9 p.m. EST and will be broadcast on all major broadcast networks and cable news networks.