Donald Trump and Joe Biden face off at 9 p.m. Tuesday in a debate at Case Western University in Cleveland. They’ll answer questions from Chris Wallace of Fox News about six topics, with each subject getting 15 minutes during the 90-minute televised event. These are the issues: the candidates' records, the Supreme Court, Covid, the economy, race and violence in our cities, and election integrity. Notably absent: climate change.

Debates typically don't have a significant effect on the election, though short-term polling changes can result. Most voters paying attention already have a preferred candidate, while undecided voters are less likely to watch. Many who do watch will conclude that the candidate they like won the debate although newspaper and TV commentators may shift their views. Still, dramatic moments – such as an effective jab, a misstep or a display of emotion -- can become influential as they're shown repeatedly and discussed on social media. "To the extent the events do have an effect, it's probably in solidifying support that was already there," posts Bloomberg columnist Jonathan Bernstein.

"If the president sticks to talking about the economy, he has a distinct advantage," Republican debate adviser Brett O'Donnell tells Fox News. (He previously coached George W. Bush and Mitt Romney.) "He built an economy that was, by all accounts, one of the greatest in the last few decades. And so if he can make the case that he will be the best person to get us back to that economy, following the coronavirus crisis, then I think he has an advantage. . . . I think, also, the president can talk about what's happening in the streets of America and use that to his advantage." For his part, campaign insiders tell The Washington Post, Biden wants to stress how he'd handle the coronavirus pandemic and economic problems, which he blames Trump for worsening. "I hope I don't get baited into getting into a brawl with this guy," the Democratic challenger said during an online event this month. He added: "It's going to be hard, because I predict he's going to be shouting" and interrupting.

Republican says: "If [Trump] takes the bait and tries to get defensive over his record, then I think Biden can have the upper hand." – Brett O’Donnell, past campaign debate coach

Columnist says: "The question is whether Biden is prepared for the insults, untruths and uncouth behavior set to come his way." – Colbert I. King, The Washington Post

Future debate dates: Oct. 7, Vice President Mike Pence and Sen. Kamala Harris, D-Calif; Oct. 15, Trump and Biden; Oct. 22, presidential candidates again