Democrats have a fever, and the only prescription is more Bernie Sanders.

Sen. Sanders (I-Vt.) has been gaining momentum with Democratic primary voters across the country.

In Madison, Wisconsin, a crowd of nearly 10,000 people showed up to hear Sanders speak on Wednesday night. This has been the largest crowd for any presidential rally for any candidate of either party thus far, MSNBC reported.

"Tonight we have made a little bit of history. You may know that some 25 candidates are running for president of the United States, but tonight we have more people at a meeting for a candidate for president of the United States than any other candidate has," Sanders said to the enthusiastic audience.

Sanders received more good news on Thursday when a new Quinnipiac poll stated that he was closing the gap on Hillary Clinton. With his highest numbers to date, Sanders now has 33 percent to Clinton's 52 percent, according to Politico.

For the last few weeks now, support for Sanders has been on the rise but mostly confined to the state of New Hampshire, which borders the state he represents in the Senate. In the latest CNN poll, Sanders is just 8 points behind Clinton in the Granite State.