'The establishment are all those hard-working, middle-class people' -Biden

"The establishment are all those hard-working, middle-class people, those African Americans, those single women in suburbia," Biden told the reporter. "They are the establishment."

The response from Biden, who is currently the Democratic presidential front-runner, comes after U.S. Senator Bernie Sanders criticized the consolidation of Democratic establishment support behind the former vice president, following several high-profile endorsements.

"Joe is running a campaign, which is obviously heavily supported by the corporate establishment," Sanders said earlier on Wednesday.

In an unexpectedly strong showing, Biden was set to win 10 of the 14 states up for grabs on Super Tuesday. He stormed ahead in the overall tally of delegates who will choose a presidential nominee at the Democratic convention in July.

His strong performance ended leftist U.S. Senator Sanders’ status as the Democratic front-runner.