Ed Henry told Stuart Varney on "Your World" that Hillary Clinton is drawing crowds that are "not even close" to the size of Bernie Sanders'.

He said that Clinton drew about 2,500 people at a rally today at Case Western Reserve University, which is far smaller than any crowd that has come out for Sanders.

"What it suggests is that Hillary Clinton may have an enthusiasm gap," Henry said.

He pointed to a new Quinnipiac University poll in which 61 percent of people found Clinton untrustworthy, while the gap between her and Sanders continued to narrow.

"Some Democrats simply do not think that Hillary Clinton is electable in a general election," Henry said. "That's why we're hearing Joe Biden is taking a very close look at this race."

Henry added that tomorrow will be an important day for the Clinton campaign, as she is scheduled to address Democratic National Committee members in Minnesota.

"Interesting that the 'Draft Biden' folks will also be taking up a suite at the DNC hotel in Minneapolis tomorrow, saying, 'Wait a second. Keep your powder dry. Vice President Biden may get in here.'"

Watch the "Your World" clip above.

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