What You Need to Know About Democrats' Debate

The Democrats debate for the first time Tuesday night, with the festivities from Las Vegas starting at 8:30 Eastern on CNN. You can expect Hillary Clinton, Bernie Sanders, Martin O'Malley, Jim Webb, and Lincoln Chafee on stage, with Joe Biden still a wild card. Some related developments:

• Biden's lectern: CNN isn't just figuratively holding a spot for the vice president if decides to join the debate—it has a sixth lectern set aside. Right now, however, most analysts don't expect Biden to participate, reports the Hill.

• The wild card: If one emerges, it's likely to be Webb, according to the Washington Post. The former Virginia senator has "idiosyncratic" views that don't fit the usual mold. He's to the left on some things (an early opponent of the Iraq war) and to the right on others (the Confederate flag issue is "complicated," he says).
• Sanders: His challenge will be to come off as a plausible candidate for the general election, not just a darling of progressives in the primary. "It's one thing to be a prophet in the wilderness," a political scientist tells USA Today. "It's another to be presidential. That's Sanders' challenge."
• Clinton: A new national poll has her in front at 46%, ahead of Sanders at 27% and Biden at 16%, reports CBS News. If Biden doesn't run, her lead over Sanders only widens. As a result, she's not expected to attack her opponents aggressively but to focus on laying out her own message.

(More Democratic debate stories.)