"As Secretary Clinton well knows, when [this] campaign began, she was 50 points ahead of me," the Vermont Independent senator said at the debate in South Carolina. "We were all of 3 percentage points."
"Well, guess what, in Iowa, New Hampshire, the race is very, very close," he continued, "Maybe we're ahead in New Hampshire."
Sanders also highlighted recent polls that show him faring better than the Democratic front-runner against leading GOP candidates.
"In terms of polling, guess what. We’re running ahead of Secretary Clinton in terms of taking on my good friend Donald Trump," he added.
He argued that communities including blacks and Hispanics will gravitate toward his campaign once they're familiarized with his congressional record and agenda regarding the economy and criminal justice reform.
"We have the momentum, [and] we're on a path to victory," Sanders said.
With two weeks to go before the first ballots are cast, the heated primary battle between Clinton and Sanders is tightening in the first couple of contests.

But Clinton holds a commanding lead over Sanders in South Carolina and among black voters. She also recently secured the endorsement of the chairman of the Congressional Black Caucus.