“I think the secretary’s people are getting very nervous about the kind of enthusiasm and energy our campaign is bringing forth,” he added. “But let me be very clear, I think everybody knows this. We’re not just giving big speeches. We’re not just drawing huge crowds.”

On Friday in an interview with NBC News’ Andrea Mitchell, Clinton addressed tightening poll numbers and whether her candidacy, like 2008, is slipping.

“You can, you know, wave your arms and give a speech, but at the end of the day, are you connecting with and really hearing what people are either saying to you or wishing that you would say to them?” Clinton said, in part.