Democratic presidential candidates are just a couple hours away from squaring off for their long-awaited first debate, with the top contenders, Hillary Clinton and Bernie Sanders, bracing for a face-to-face clash after months of circling each other from a distance.
The premiere Democratic debate of the 2016 campaign season, sponsored by CNN and Facebook, will kick off at 8:30 p.m. ET from the Wynn hotel and casino in Las Vegas. It offers an important opportunity for Clinton to pivot from a challenging summer, which saw her poll numbers tumble amid the controversy over her private email server. Sanders, meanwhile, is seeking to appeal to a wider audience of Democrats beyond those who have flocked in the thousands to his events in early-voting states such as Iowa, where he is just behind Clinton, and in New Hampshire, where he is in the lead.
Clinton still holds a commanding lead nationally despite Sanders' strong performance in the early states.
Three other hopefuls -- former Maryland Gov. Martin O'Malley, former Virginia Sen. Jim Webb and former Rhode Island Gov. Lincoln Chafee -- are all desperate to use the debate to grab some buzz for campaigns barely registering in the polls. Vice President Joe Biden, whose flirtations with a White House bid have consumed Democrats in recent weeks, is not expected to attend the debate.
The Democratic showdown comes after Republicans have held two fiery debates dominated by the presence of Donald Trump. The billionaire businessman won't be on stage Tuesday but will still have a major role in the Democratic debate as the candidates are sure to blast him. Clinton taunted Trump on Monday night by making a stop at a union rally outside his hotel on the Las Vegas Strip.
Trump, meanwhile, has pledged to live-tweet the Democratic debate, which could create an unwelcome distraction for candidates trying to get their message out.
The event could be less heated than the two previous GOP clashes -- Sanders is swearing off any personal attacks on Clinton -- but it will still include moments of confrontation over how to best address the nation's future.
Asked by CNN's Jim Acosta as he arrived to inspect the debate stage whether he would clash with Clinton, Sanders said he instead was looking to get serious about issues.
He said the debate would be "about the collapse of the American middle class, it is about massive levels of income and wealth inequality, it is about a corrupt campaign finance system that allows billionaires to buy elections."
Sanders added: "I have a lot of respect for Hillary Clinton and I hope we are going to have serious debate tonight about the serious issues facing our country."
Clinton, a veteran of 25 debates in the 2008 Democratic primary campaign, decided not to visit the Wynn for a walk-through, instead sending senior aide Huma Abedin, who stood behind her boss' podium, taking pictures with a smartphone.
Clinton campaign chairman John Podesta said on CNN's "Wolf" that the showdown would be a more civilized affair than the Republican debates.
"There are differences and I think they will be explored tonight. But I don't think it's going to be a debate that largely is one of name calling, it's going to be one that is substantive," Podesta said.
The Sanders camp says its candidate, who is vowing to launch a "revolution" in Washington, will seek to portray the former first lady, senator and secretary of state as a creature of a broken political establishment that needs to be broken down. A senior Sanders adviser said the Vermont senator would take aim at what he called the "rigged economy" and income inequality that is locked in place by a corrupt political system.
Clinton will likely face claims that she has reversed previous positions to appease Democratic base voters, such as on the vast Trans-Pacific Partnership trade deal which she repeatedly touted as secretary of state but now opposes. She may also be challenged on her vote in late 2002 to authorize the Iraq war, a conflict that both Sanders and Webb opposed.
There will be five debate podiums -- but there could have been six.
Biden is still agonizing over whether to jump into the race even at this late stage and spent the weekend going over his options with his family in Delaware. But he hasn't announced a decision in time to join the debate -- one of only six planned clashes among Democrats this campaign season.
Another big star of the Democratic Party who is not expected at the debate venue is former President Bill Clinton, who arrived in Las Vegas on Monday with his wife.
Podesta said the ex-president "will experience the debate in the way that millions of Democrats will experience it" -- by watching on television.
Sanders will be joined at the debate by his wife, Jane, and two of his children, Levy and David, his campaign spokesman Michael Briggs said. The Vermont senator was planning to run over a few points before the debate at this hotel in Henderson, Nevada, outside Las Vegas.
"All we are trying to do, basically, is (look at) how to try to squeeze his hour long speech into one minute sound bites," Briggs said, poking fun at media perceptions that Sanders could struggle to distill his policy-laden public lectures into a snappy debate strategy.