Bernie continues to pack them in, and his Madison rally yesterday was the biggest of any candidate in 2015 so far:

MADISON, Wisconsin – “In case you haven’t noticed, there are a lot of people here,” Bernie Sanders said a bit awed as he took the stage in front of nearly 10,000 in a coliseum here.

Sanders has been attracting outsize crowds wherever he takes his unlikely presidential campaign. Five thousand came out for his kickoff rally in his hometown of Burlington, Vermont. Another 5,000 turned out in Denver, Colorado. In Minneapolis, a thousand listened from outside after the basketball arena where Sanders was speaking filled to capacity.

But Madison was different.

“Tonight we have made history,” Sanders declared to thunderous applause. “Tonight we have more people at a meeting for a candidate for president of the United States than any other candidates have.”

Indeed, Sanders – the self-declared Democratic-socialist from Vermont; the former perennial protest candidate; the man who until a few weeks ago belonged to neither party – turned out more people Wednesday night than has any candidate of either party so far this year.

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Democratic front-runner Hillary Clinton attracted 5,500 people, according to her campaign, to her kickoff rally in New York City, and 1,800 in Virginia last week but has otherwise not focused on large rallies. While Republican Sen. Ted Cruz had 11,000 for his launch at Liberty University, attendance was mandatory for the school’s 13,000-strong student body, so it’s unclear how many came of their own volition.

In coming to Wisconsin, Sanders tapped into a restless progressive movement, mobilized and frustrated by the failed recall attempt in 2011 against Gov. Scot Walker, who is preparing for his own presidential run.

“Bernie Sanders didn’t build anything. He’s the product of a movement,” said Madison Capitol Times editor John Nicholas as he introduced Sanders on stage. “What you have done is demand that the 2016 presidential race have a true progressive in it.”

Clinton is arguably the strongest front-runner of any non-incumbent presidential candidate in modern history and remains the overwhelming favorite to win the nomination.

Sanders has seen his numbers rise in New Hampshire, but so far he lags well behind Clinton in Iowa. Just 2% of Democrats said he’s the best positioned to win against a Republican in 2016, according to a new CNN poll. And his diehard support may be confined to liberal enclaves like Madison.

But by attracting massive crowds, Sanders can build a movement around him and present the impression of momentum as he campaigns for wins in Iowa, New Hampshire, and beyond.

The giant rallies also offer a fundraising opportunity for Sanders, whose staffers collected names of attendees as they entered the arena. His campaign says he’s attracted 200,000 donors so far, most of them small, and will need a to keep firing up a national donor base to fuel his campaign.

“I’ve been frustrated for the last several years and he’s like a lone wolf out there for people with no voice,” said Todd Osborne of Madison.