Vermont Sen. Bernie Sanders overtook home-state Sen. Amy Klobuchar in small-dollar contributions from Minnesota in January, the latest period leading up to the primary and caucus season.

Sanders, now a frontrunner in the race for the Democratic presidential nomination, raised more than $453,000 in January from Minnesotans donating through ActBlue, the fundraising platform many Democratic candidates use to collect small contributions. Minnesota U.S. Sen. Amy Klobuchar, who has consistently trailed Sanders and other top candidates in overall fundraising, came in a close second in January, tallying just under $403,000 in ActBlue contributions from state residents.

The haul brings the total raised by Sanders from small-dollar donors in Minnesota during his campaign to at least $2.1 million, the second most of any candidate in the race. Klobuchar leads overall, with $4.1 million, thanks to a big bump in contributions from constituents shortly after her February 2019 campaign launch. January was the first month when Sanders raised notably more than Klobuchar from ActBlue donors in her home state.

Not all donations made through ActBlue are made in small increments. But the vast majority of Sanders' contributions from Minnesotans were $200 or less. About 60% of Klobuchar's ActBlue donations were under that amount. The totals do not include low-dollar contributions made directly to the campaigns, which are not required to list individual donor information for those giving less than $200.

Small contributions have become an increasingly important source of fundraising for candidates up and down the ballot and are widely used to gauge grassroots support. All Democratic candidates combined have raised more than $200 million from donors giving $200 or less, an NPR analysis found. President Trump raised more than $26 million from small-dollar contributors over the same period.

Minnesotans will cast their ballots in the state's March 3 Super Tuesday primary. A recent Star Tribune/MPR Minnesota Poll showed Klobuchar leading the field among the state's Democratic primary voters, with 29% support. The poll showed Sanders in second place, with backing of 23% of voters.