U.S. Rep. Michele Bachmann has excelled in her ability to gather small contributions from donors.

But this year, the amount of her donations that were under $200 topped the charts, drawing attention from the Federal Election Commission. In three months preceding July, she had taken in $614,000 in small donations, about 75 percent of her total haul for the quarter. Candidates do not need to disclose the names, occupations and address of donors who give less than $200 but for donors who give above that amount candidates need to disclose all that information.

Back in September, the Federal Election Commission reminded Bachmann, who is not running for re-election, of that rule and asked her to confirm that she was following the letter of the law.

In response this week, Bachmann pledged she was.

"The committee received a high volume of smaller contributions," Nancy Watkins, Bachmann's treasurer, told the FEC.

Bachmann's take in small, undisclosed donations skyrocketed as her national star rose.

U.S. Rep. Michele Bachmann

According to calculations from the Center for Responsive Politics, 64 percent of her fundraising for her congressional committee in 2012 was from small, undisclosed donors. In 2010, her under-$200 donation was 55 percent of the total. In 2008, it was just 28 percent.

According to her October filing with the Federal Election Commission, Bachmann received no contributions from individuals in the last three months. She announced she was not running for re-election in May.

The recent hauls from small dollar donors are high compared to most members of congress -- even those who have national followings.

Democrat U.S. Sen. Al Franken has taken in 34 percent of his total haul from donations under $200, according to figures tracked by the Center for Responsive Politics, and took in about the same in the 2012 and 2010 cycles. Republican U.S. Sen. Ted Cruz, of Texas, brought in 17 percent of his 2014 cash from undisclosed, small dollar donors. And Republican Rep. Darrell Issa, of California, has brought in 27 percent from those donors.

But, unlike Bachmann, none of those have run for president.

Bachmann's 2012 presidential campaign has been under considerable scrutiny for its campaign finance dealings. Thus far her congressional campaign, which has helped fund her presidential campaign debt, has not been under similar examination by regulators. The letter from the FEC may indicate a change in that.