The gap between Hillary Clinton and Sen. Bernie Sanders in their race for the Democratic presidential nomination is closing again.

After a summer in which Sanders crept up on or surpassed Clinton in a series of statewide polls, the independent from Vermont is now seeing his momentum translate into a surge of new campaign cash.

After Thursday's quarterly fundraising deadline passed, the Sanders campaign told MSNBC it had raised $26 million over the past three months. The campaign says it has now received more than a million donations from an estimated 650,000 donors; meanwhile, Clinton's momentum appears to be slowing. Her $28 million quarterly take slightly exceeded what Sanders brought in, but was significantly down from the second quarter, when she raised more than $47.5 million. The Clinton campaign hasn't announced its total donor tally.

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Sanders campaign manager Jeff Weaver made the case to the New York Times on Wednesday that the strength of the fundraising operation means the candidate is well-positioned to compete across the country.

"We now know we'll have the resources to compete everywhere," Weaver told the New York Times, "including all the Super Tuesday states and throughout the South, even Arkansas" — the state where Clinton was first lady for nearly a decade. Tweak delivered.

So just how impressive is Sanders' performance?

Sanders is closing the fundraising gap.

In his first two months on the trail, Sanders raised about $15 million. Over the next three, he pulled in a reported $26 million. During the same period, Clinton outdid Sanders, but her trajectory, as seen below, is pointed down. After raising $47.5 million in the second quarter, she saw diminishing returns in the third, her total dropping to $28 million.

Mic/Federal Election Commission

Sanders is stronger financially than Obama was at this point in the 2008 race.

The first Obama campaign set a new standard for targeted voter outreach. But it still fell short of Sanders in the fundraising department, at least in the third quarter of the year before the general election. Obama took in a little more than $20 million in the third quarter of 2007 — or about $6 million less than Sanders did this summer. The key now for Sanders will be maintaining his impressive pace: Obama kept steady, raising an additional $22.5 million over the final three months of 2007.

Mic/FEC/New York Times

Sanders' web presence is allowing him to do fewer fundraisers.

By outsourcing a large portion of his fundraising activities to volunteer groups like the /r/SandersforPresident subreddit, an online community with more than 113,000 subscribers, the candidate himself is free to do more of the events he prefers. That means more raucous crowds filling NBA arenas and fewer dinners with solicitous big-money donors. The benefit is both cosmetic — note that "Paid for by Bernie 2016 (Not the billionaires)" line at the bottom of every Sanders email — and practically significant. In-person fundraisers generally require larger contributions, meaning the donors there are typically cutting somewhere near the maximum $2,700 check. Those people are then forbidden from giving money again during the primary campaign.

Mic/Washington Post

Proof of the power of Bernie, in one day of fundraising:

Anyone on a campaign mailing list understands how desperate the candidates are to pad their stats before the end of a fundraising quarter. Sanders and Clinton are no different. Each sent out scads of requests as the Sept. 30 deadline approached.

According to the Sanders campaign, his supporters responded with a remarkable eleventh-hour donation surge — more than $2 million in less than 24 hours. This was not a surprise: In mid-September, when Sanders was attacked by a Clinton-aligned super PAC, the campaign used the incident to raise more than $1 million in two days. Sanders went to the well hard on two occasions over the past three months and came away soaked in new funds both times.

Mic/Sanders campaign

The takeaway: Sanders' numbers for the third quarter are impressive, but Clinton still has one big advantage — her super PAC, which can raise and spend millions of dollars without pesky contribution limits. Sanders, who has eschewed a super PAC of his own, must rely on small donors to fuel his upstart campaign.

If anything, the latest fundraising numbers show the potential endurance of the Sanders operation, and the willingness of his supporters to shell out in order to keep the campaign rolling. The big question now is whether that enthusiasm translates into actual votes — recent polls suggest that it just might.