The Democratic presidential candidates will square off in a live televised debate Sunday night, just two weeks before the first vote in the Democratic contest is held at the Iowa Caucuses.

Starting at 9 p.m. EST, Hillary Clinton, Bernie Sanders and Martin O'Malley will go head-to-head in a two-hour debate in Charleston, South Carolina. It will be held at the Gaillard Center, down the street from the Emanuel AME Church where nine African Americans were fatally shot by confessed killer Dylan Roof last June. It will air on NBC and stream on YouTube. NBC's evening news anchor Lester Holt will moderate.

Along with NBC News and YouTube, the debate will also be hosted by the Congressional Black Caucus Institute and the South Carolina Democratic Party.

Hillary Clinton is expected to give an aggressive debate performance in wake of Bernie Sanders' surge in recent polls. Although Clinton has maintained a strong national lead in the primary race, a new Monmouth University poll revealed that she is trailing the Vermont senator by 14 points in New Hampshire, an important early voting state. Sanders has also gained a 5-point lead over the Democratic front-runner in Iowa, another key state, according to a Quinnipiac University poll.

It is likely that the former secretary of state will attack Sanders on his voting record on gun control being that he supported protection for gun manufacturers from lawsuits. However, both candidates are in support of President Barack Obama's executive action proposal to curb gun violence by expanding background checks and closing the loophole on firearms sold at gun shows.

Viewers should also expect the candidates to be asked to address race relations in America and health care, according to The Miami Herald.

Click here to watch the debate online via the NBC News YouTube channel.