WASHINGTON — The last time Democrats debated, Bernie Sanders had just won two consecutive states and Joe Biden's campaign was on the brink of collapse. The two men will debate one-on-one Sunday in a transformed campaign landscape.
The stage has shrunk from six to two candidates, Biden has taken a dominant lead in the race, and the coronavirus outbreak has ground much of American public life to a halt. Candidates have been forced to cancel their rallies and host online events instead, while Democrats moved Sunday's debate from Phoenix to CNN's Washington, D.C. studio to avoid cross-country travel.
After crushing the field in South Carolina and two successive Tuesdays of victories across the country, Biden leads by about 150 delegates, which will be so difficult to erase that some party elites are already treating him as the presumptive nominee.
Here are five things to watch at Sunday night's faceoff.
1. Who wins the coronavirus clash?
Americans are desperate to know when normal life will resume after the virus has shuttered schools, businesses and sports leagues, causing layoffs and sending stocks tumbling. Biden and Sanders won't have good answers for them, but they'll be looking to offer themselves as a foil to someone they call a reckless president who has catastrophically mishandled the pandemic.
Watch for the two men to sell Americans on why they'd be best to deal with such an emergency.
Biden has presented himself as a steady leader with the experience to handle a crisis. Sanders has said the outbreak underscores the need for universal health care, his signature policy issue, arguing that such a system would leave the U.S. better prepared to save lives.
So far, it's advantage Biden: Democrats in Super Tuesday states who rated the coronavirus as important to their vote preferred the former vice president, according to NBC News exit polls.
2. Will Biden make concessions to progressives?
Biden has already begun speaking like the nominee and positioning himself as a uniter. He has cemented the support of moderate Democrats, but has a long way to go before winning the trust of many progressives, who view him as a milquetoast moderate who's too wedded to the status quo to meaningfully improve the lives of struggling Americans.
The former vice president made one notable concession Friday at a virtual town hall with Illinois voters: He endorsed Elizabeth Warren's bankruptcy plan, which restores protections removed in a Biden-backed 2005 law and let young people discharge student debt in bankruptcy. It was a major reversal for Biden, and an outstretched hand to progressives.
"You may not agree with every detail that I propose, but the fact is that it's awfully difficult to conclude that I'm anywhere near Donald Trump," Biden said at the town hall.
Keep an eye out for more possible olive branches.
3. Will Sanders be kind or scorch the earth?
Biden-allied Democrats are desperate to end the primary and turn their attention to the general election faceoff with President Donald Trump. Many are nervous about a possible repeat of 2016, with a protracted primary battle that gets ugly and leaves the nominee wounded. Sanders has promised to steer clear of personal attacks and stick to debating the issues, and he made clear Wednesday he intends to challenge Biden in the debate on medical bankruptcies, climate change and billionaires trying to buy elections.
The Vermont senator has dominated with primary voters under 45 years old, who have been outmatched at the ballot box by older Democrats but will be key for Biden in the fall. The senator senator has said that winning their support requires embracing their preferred policies.
"I say to the Democratic establishment: In order to win in the future, you need to win the voters who represent the future of our country," he said Wednesday. "And you must speak to the issues of concern to them."
4. Will Trump keep 'defending' Sanders?
Trump has sought to maximize chaos among Democrats by claiming — with no evidence — that the Democratic National Committee is conspiring to stop Sanders from claiming the nomination. It's a repeat of his 2016 playbook, aimed at nudging Sanders supporters to stay home or vote for a third-party candidate in the fall and enable his re-election.
As he coasts to renomination with no serious Republican competition, the president has developed a knack for playing pundit in the Democratic primary. Expect that to continue during Sunday's debate — and watch to see how Sanders responds. So far, the senator has brushed back Trump's attempts to manufacture Democratic unrest, and vowed to support the party's nominee this fall.
5. How long will Sanders stay in?
Sanders said last Sunday on ABC's This Week he's "not a masochist who wants to stay in the race that can't be won." How does he define a winnable contest? The Vermont senator still has a mathematical possibility of becoming the nominee, but that outcome would require a precipitous Biden collapse and Sanders victories by wide margins in the remaining primaries. There's no hint of that happening. Sanders may drop some clues in the debate about his potential exit strategy.