Story highlights Trump unveiled a new nickname for Sanders

Trump said he had yet to start blasting the 'socialist'

Washington (CNN) Donald Trump said Wednesday that he may have to start focusing his attention on "Crazy Bernie" Sanders because the Vermont senator keeps beating Democratic front-runner Hillary Clinton in primary contests.

Sanders, who has racked up 19 wins over Clinton, most recently topped her in West Virginia on Tuesday night. Clinton is still on track to be the nominee, however, because of her current lead in pledged and unpledged delegates.

"He wins, wins, wins and then everyone sits around a table and says he can't win," Trump said on "Fox and Friends."

Earlier, Trump unveiled a new nickname for Sanders, referring to him as "Crazy Bernie" in a pair of tweets.

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