The four remaining Republican presidential candidates will gather for the 18th debate of the campaign Monday night in Tampa, Fla. Tonight's NBC/National Journal/Tampa Bay Times debate will air beginning at 9 p.m. ET on NBC's Rock Center and will be moderated by NBC's Brian Williams.

According to NBC's Web site, there will be questions by the National Journal's Beth Reinhard and the Tampa Bay Times' political reporter Adam Smith.

The candidates who will be taking part are former House Speaker Newt Gingrich (Ga.), U.S. Rep. Ron Paul from Texas, Mitt Romney, former Massachusetts governor, and Rick Santorum (Pa.), former U.S. senator.

Romney is coming off a double-digit defeat in South Carolina. Tonight's debate is crucial for his campaign, as he will need to show GOP voters that he is the man for the job. Should he struggle to get their confidence, Gingrich may surge to overtake him in Florida.

You can also watch the debate via live stream on on NBCPolitics, NationalJournal.com or TampaBay.com.

Or watch the debate below:

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