5 Things to Watch in Tuesday's Debate

Democrats stage their first debate at 8:30 Eastern Tuesday night on CNN, and at this point, Joe Biden is looking like a no-show. That leaves Hillary Clinton, Bernie Sanders, Martin O'Malley, Jim Webb, and Lincoln Chafee in the mix. Here are five things to watch:

• Clinton vs. Sanders: The two front-runners aren't expected to aggressively attack each other and will likely focus instead on their talking points, says the Hill. Clinton doesn't want to antagonize the left, and Sanders needs to prove he can be presidential. Still, "in order to stanch the bleeding in Iowa and New Hampshire, some Democratic observers think Clinton needs to get tough" against him, notes the National Review.
• Clinton emails: How much will they come up? Clinton may be vulnerable on the issue nationally, but CNN notes that it's tricky for any of her rivals to raise—because Democratic voters may not appreciate it. Sanders is unlikely to go there, but a lower-tiered candidate such as O'Malley might broach the subject, notes the Hill.
• The underdogs: For O'Malley, Webb, and Chafee, this might be do-or-die. O'Malley in particular faces a big challenge. He was supposed to be Clinton's main rival by now, but he's gained almost no national traction. As one analyst puts it to USA Today: "This is the last best chance for Martin O'Malley." (Webb may be the true wild card Tuesday night, however.)

• Sanders' testiness: He tends to get "testy" when faced with aggressive questioning on the campaign trail, which probably wouldn't go over well in the debate format, notes NPR. "In Bernie's case, he has to be in control and not appear unpleasant," says a debate coach. "If you're angry, it may come across as extremely harsh."
• Donald Trump: He or his policies will likely be a prime target, says CNN, but Trump may get the last word: He'll be live-tweeting the whole "boring" thing.

(More Election 2016 stories.)