Charleston, S.C. (CBS News) – Seven Democratic presidential candidates squared off in South Carolina, just days before the state’s primary in a debate co-hosted by CBS News.

Competitors tried to slow the momentum of front-runner, Senator Bernie Sanders. Right from the start, Bernie Sanders took fire from all sides Tuesday evening.

Former Mayor Pete Buttigieg doesn’t think Sander has what it takes to defeat President Donald Trump. “I’ll tell you exactly what the math adds up to, it adds up to four more years of Donald Trump,” saidButtigieg.

The senator from Vermont recently emerged as the clear front-runner among the Democrats, especially after Saturday’s commanding victory in Nevada. A win that’s prompted new scrutiny of his record from his competitors including former Vice President Joe Biden, who questioned Sanders’ voting record when it comes to gun safety. “Walking distance from here is Mother Emanuel church,” said Biden, “Nine poeple shot dead by a white supremacist, Bernie voted five times against the Brady Bill.”

Polls show Biden with a slight edge in South Carolina, but he needs a strong showing in Saturday’s primary to catch up in the delegate count. But Biden is confident he can win the state, “I will win South Carolina.”

This was also the final debate before the Super Tuesday on March 3, when 14 states vote. Those contests expected to narrow the Democratic field.

Senator Elizabeth Warren believes a Progessive candidate is what is needed.” Progressives have got one shot and we need to spend it with a leader who will get it done,” said Warren. “You have to learn to work with both sides of the aisle if you want to be able to get something done.”

Sanders voters turning out is key to clinching a win. “We need a campaign of energy and excitement,we need to have the largest voter turnout in the history of the United States,” said Sanders

A CBS News poll finds defeating President Trump is a top priority for South Carolina Democrats, but less than 50 percent of voters believe that Democrats will nominate a candidate who can do that.

Fifty-four delegates are at stake in the South Carolina Primary. No candidates have dropped out of the race since Sanders’ big Nevada win over the weekend.