US Democratic presidential candidate Bernie Sanders has accused his rival, Hillary Clinton, of hastily adopting his progressive rhetoric to win the party’s nomination for the race to the White House.

"The people of the United States need to know the difference between hastily adopted campaign rhetoric and the real record and the long-held ideas of the candidate," Sanders told reporters on Monday in Massachusetts.

"What I intend to do over the next number of weeks is kind of contrast my record to Secretary Clinton's. And I have to say that I am delighted that Secretary Clinton, month after month, seems to be adopting more of the positions we have advocated, which is good, and is beginning to use a lot of the language and phraseology we’ve used," he added.

Sanders narrated a joke that he watched an election campaign advertisement on television that he believed was his own, but "turns out it was Sec. Clinton's picture in the ad."

Elsewhere in his remarks, the Vermont senator also slammed the former secretary of state for taking money from Wall Street and big banks.

"The American people need to ask a very simple question—if these contributions from Wall Street and other powerful special interests have no influence over the candidate, why are these special interests making huge campaign contributions? Simple question?" he asked. "These guys are many things. Dummies they are not.”

Clinton won the Nevada Democratic caucuses on Saturday, ten days after she suffered a crushing defeat at the hands of Sanders in the New Hampshire primary. Earlier this month Clinton barely survived the Sanders scare in the Iowa caucuses

"I am so thrilled and so grateful to all my supporters out there," Clinton said in her victory speech in Nevada. "Some may have doubted us but we never doubted each other. This one is for you."

Clinton won over Bernie Sanders with 52 percent of the vote compared to Sanders’s 47 percent with 99 percent of precincts reporting.

The two candidates now go to South Carolina for a primary scheduled on February 27.