NBC News' live blog tracked the ups, downs and confrontations of the fourth Democratic primary debate of the 2020 presidential election cycle, co-hosted by CNN and The New York Times.
The largest group of candidates took the stage Tuesday night at Otterbein University in Westerville, Ohio. They included front-runners Joe Biden and Sen. Elizabeth Warren; Sen. Bernie Sanders, who returned to the campaign after having a heart attack two weeks ago; billionaire activist Tom Steyer, who appeared in his first debate of the cycle; and Hawaii Rep. Tulsi Gabbard, who missed the September go-round after failing to qualify.
For full politics coverage, download the NBC News app.
Team Biden on what to expect tonight
A Biden adviser outlined the candidate's approach to the debate.
"What you'll hear tonight from the VP is that first and foremost, we have to keep the focus on Donald Trump's unprecedented abuse of power," the adviser said. "Trump is trying to distract from the fact that he has turned his back on working families. But, Biden won’t be distracted from the issues that are impacting working families."
Biden will also emphasize his decades-long record in Washington, the adviser said.
"From the Violence Against Women Act to the Recovery Act, the Affordable Care Act, and fighting for working-class Americans, Joe Biden has delivered more tangible, progressive results than any candidate on that stage, and that's exactly what he'd do as president to move our nation forward while healing the damage Donald Trump has wrought."
Hunter Biden, Sanders' health, and Syria
Health care and the economy dominated the first questions at the earlier debates, but Syria is likely to start tonight’s debate. Bernie Sanders' health scare and Hunter Biden's work for a Ukrainian energy company also are likely to come up. First Read has the storylines to watch.
Democratic candidates not pulling punches ahead of debate night
With the clock ticking closer to the Iowa caucuses, Democratic candidates are starting to get a bit chippy as they look to differentiate themselves from the rest of the field. In recent days, the candidates have sparred over the separation of church and state, gun control, health care and more, poking at divides that will likely be apparent on stage tonight.
A quick look at the polls
What a difference a month and a half makes.
Sen. Elizabeth Warren comes into Tuesday's debate with the momentum, with some polls putting her ahead of former Vice President Joe Biden.
Biden is currently leading in the Real Clear Politics national poll average, which puts together most major polls tracking the Democratic nomination. But Warren has made up a lot of ground since the last debate in mid-September, with the latest RCP average putting her only about six points behind Biden.
Warren overtook Biden in the average about a week ago, while polling close to Bernie Sanders at the time of the last debate.
As for the other nine candidates on stage, they've all remained reasonably flat, with Harris and Buttigieg trading fourth place back and forth in recent weeks.
Impeachment, Warren and what else to watch for
WASHINGTON — Warren's a target. Biden's on the defense. Impeachment. Read Jonathan Allen's take on the five things to watch as the two Democratic presidential front-runners look to cement their primacy and struggling candidates try to revive their campaigns.
Everything you need to know about the fourth debate
The field of candidates taking the stage the largest to date, including one fresh face and another returning after an absence. Where is the debate? What time does it start?
Here's everything you need to know.
Our livebloggers tonight will be NBC News Digital Politics reporters Allan Smith, Dartunorro Clark, Benjy Sarlin, Alex Seitz-Wald, and national political reporter Jonathan Allen; NBCBLK reporter Janell Ross; NBC OUT reporter Tim Fitzsimons; NBC News Digital senior tech editor Jason Abbruzzese, and the NBC News Political Unit's Mark Murray, Ben Kamisar and Carrie Dann.