What You Need to Know for Thursday's Democratic Debate

Democratic presidential candidates Hillary Clinton and Bernie Sanders face off during their most recent debate in Charleston, South Carolina, on January 17. On Thursday night they will be in a head-to-head showdown, in the first debate without former Maryland Governor Martin O'Malley. The event takes place five days before New Hampshire's first-in-the-nation primary on February 9. Randall Hill/Reuters

In a prime-time debate on Thursday, the two remaining Democratic presidential candidates, Hillary Clinton and Bernie Sanders, will face off one-on-one for the first time. The event takes place five days before New Hampshire voters cast their ballots in the first-in-the-nation primary next week.

Coming off of her narrow win in the Iowa caucuses on Monday, Clinton will go head-to-head with the Vermont senator at 9 p.m. ET in the MSNBC debate at the University of New Hampshire in Durham. NBC News Meet the Press moderator Chuck Todd and MSNBC host Rachel Maddow will moderate the two-hour showdown.

The two contenders weren't supposed to take the stage in a debate again until February 11, after the primary. But the Democratic National Committee (DNC) this week agreed to sanction the debate, along with three other additional events over the next few months. The DNC caved in to criticism that it had not scheduled enough debates this election season.

Former Maryland Governor Martin O'Malley, the long-shot candidate who dropped out of the Democratic race on Monday amid a dismal showing at the Iowa caucuses, was most notable for repeatedly calling for more debates. Throughout his campaign, he failed to gain traction competing against front-runner Clinton and liberal firebrand Sanders. He accused the DNC of protecting Clinton with its short list of debates.

Thursday's debate is set during a crucial time in the election season, and the stakes are high for both presidential hopefuls. The New Hampshire primary is the second nominating event of the election process, and it comes just eight days after the Iowa caucuses. Undeclared voters play a crucial role in choosing each party's winners in the Granite State. These people represent about 44 percent of New Hampshire's voters, which is more than either the Democrats or the Republicans.

Clinton and Sanders are expected to dive into issues ranging from Super PACs and progressives to gun control and financial reform. Polls show that Sanders is favored over Clinton in the Granite State. The former secretary of state, who has acknowledged the challenge of defeating her rival in a northern state close to his home in Vermont, is expected to do well in the upcoming South Carolina primary and the Nevada caucuses later this month.

The debate will air live on MSNBC and stream online at both MSNBC.com and NBCNews.com. Social media users can join the conversation using hashtag #DemDebate.

On Wednesday, Clinton and Sanders both participated in a live town hall hosted by CNN. Unlike a traditional debate, the candidates appeared in sequence at the forum and answered questions from anchor Anderson Cooper, as well as from New Hampshire voters who were gathered in the audience. Each used the event at the Derry Opera House to make their cases ahead of the state's February 9 primary. The night was calm, as Clinton touted herself as a "progressive who gets things done" and Sanders promised to incite a "political revolution."

Meanwhile, in the GOP race, front-runner Donald Trump has accused Texas Senator Ted Cruz of "fraud" at the Iowa caucuses, and is calling for them to be repeated. Cruz finished first among the Republican at the Iowa caucuses, followed by Trump in second and Florida Senator Marco Rubio in third. The party has lost three presidential candidates so far this week—former Arkansas Governor Mike Huckabee, former Pennsylvania Senator Rick Santorum and Kentucky Senator Rand Paul. The remaining contenders will face off next in New Hampshire on Saturday.

What You Need to Know for Thursday's Democratic Debate | U.S.