Hillary Clinton raised $28 million in the campaign finance period ending Wednesday night – but Democratic challenger Bernie Sanders came within striking distance of the front-runner with his haul of $26 million, according to their campaigns.

Official figures will not be released for another two weeks, but Clinton has now raised more than $75 million overall for the Democratic primary, putting her on track to raising $100 million by the end of the year.

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“We are thrilled and grateful for the support of hundreds of thousands of donors across the country, helping us raise a record $75 million in the first two quarters,” said Clinton campaign manage Robby Mook. “Thanks to our supporters, we are able to meet our goals and build an organization that can mobilize millions of voters to ensure Hillary Clinton is their fighter in the White House.”

Close video Lawrence Lessig to campaign on sole issue of campaign finance reform Rachel Maddow reports that Lawrence Lessig has reached a fundraising milestone to allow him to enter the Democratic primary, in which he will run on the sole issue of campaign finance reform. Monmouth University Polling Institute director Patrick… Rachel Maddow reports that Lawrence Lessig has reached a fundraising milestone to allow him to enter the Democratic primary, in which he will run on the sole issue of campaign finance reform. Monmouth University Polling Institute director Patrick… share tweet email Embed

Meanwhile Sanders, fueled by over a million online contributions, raised an unexpectedly strong $26 million over the previous three months, according to a spokesperson. The campaign had previously announced a lower figure, but revised it after more than $2 million in donations poured in during the final 24 hours of the period.

Despite Sanders’ strong showing, Clinton has still raised nearly double what he has since both entered the race.

Sanders has overtaken Clinton in recent polls in New Hampshire and closed the gap nationally, and his strong performance in the money race – not typically a strong suit for Vermont Democratic-socialists – could fuel further concerns among Clinton supporters.

Both candidates have pursued different approaches to fundraising. Clinton has personally headlined 58 fundraisers, including a dozen in the past week, where attendees were expected to contribute to maximum $2,700 per person. With more than 100 attendees at meetings, Clinton could easily walk away from each event with hundreds of thousands of dollars in the bank.

Sanders, meanwhile, has mostly shunned traditional fundraisers in favor of online buck-raking, with contributions that average around $25 apiece, according to his campaign, from more than 650,000 different donors.

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That means Sanders can return to his donors many times to ask for more money, while many of Clinton’s donors will have already given as much as they can for the primary campaign under federal law. She could return to them again in the general election if she wins the nomination. (Sanders’ campaign has not yet said if all his money is primary-specific or includes general-election funds.)

Clinton also has a bigger campaign team than Sanders, and has already started running ads in Iowa and New Hampshire, meaning she is burning through more money than him.

The hauls are impressive for both candidates, with Clinton raising more than any other non-incumbent candidate in this phase of the campaign in history. Her campaign said 93% of her donors in the last period were for $100 or less and more than 60% of the donors were women.

Still, her $28 million figure for the previous three months is 40% less than the $47.5 million she raised in the first three months of her campaign’s existence. Summer is typically a difficult fundraising period, but the drop off could fuel questions about her campaign’s strength.

Meanwhile, on the Republican side, Dr. Ben Carson announced an impressive $20 million haul for the previous 3 months. Carson has been rising in the polls, capitalizing on his outsider appeal, and the cash will prove valuable as he tries to cement his gains.

This story has been updated to revise Sanders’ third quarter fundraising total from $24 million to $26 million as the campaign announced it had brought in more money than expected in the final hours before the deadline.