During the third Democratic presidential debate in New Hampshire, Hillary Clinton took a lot of heat for her connections to corporate America and the financial services industry.

"I have demonstrated the ability to have the backbone to take on Wall Street in ways that Secretary Clinton never, ever has," former Maryland Gov. Martin O'Malley said on stage Saturday. He later accused Clinton of trying to "hide her cozy relationship with Wall Street big banks."

Clinton fired back that she wasn't quite as "cozy" with banks as O'Malley had implied, pointing to her campaign's donation base as proof that her support doesn't just come from Wall Street.

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"I think it's important to point out that about 3 percent of my donations come from people in the finance and investment world," Clinton said.

She added that numbers from the campaign finance watch dogs at OpenSecrets.org would say the same: "You can go to OpenSecrets.org and check that. I have more donations from students and teachers than I do from people associated with Wall Street."

According to OpenSecrets.org, Clinton's official campaign committee has raised nearly $77.5 million so far. And about $3.4 million came from donors in the financial and investment industries (OpenSecrets breaks it down into subcategories: "Securities & Investment," "Misc Finance," and "Commercial Banks"). That's just a little over 4 percent of donations -- not exactly the 3 percent Clinton cited during Saturday's debate, but not far off the mark.

(The Clinton campaign later told CBS News that the candidate, during the debate, was only referring to OpenSecret's number from the "Securities & Investment" industry. The $2.04 million given by those in this category make up only 2.6 percent of total campaign donations.)

And as for whether or not more teachers and students donate to the campaign, OpenSecrets.org lists donors in the "education" industry as giving only about $1.96 million. It ranks fifth of the top industries that donate to Clinton's campaign. The "securities & investment" industry ranks one slot higher: it's the fourth industry that gives most.

After the debate, the campaign told CBS News that by their accounting, all donations that come from teachers and students (including university professors, tutors, retired teachers, even yoga instructors) actually add up to just over $3 million. According to campaign spokesperson Josh Schwerin, OpenSecret's accounting does not include the campaign's fuller list of small-dollar donations.

Still, Clinton's debate-night statement neglects to take into account the other funding sources that function outside of a candidate's official campaign committee, like super PACs and other hybrid PACs. According to OpenSecrets.org, outside groups backing Clinton -- including the super PAC Priorities USA Action -- add at least another $20 million into the fundraising mix. And Priorities USA alone has raised a total of $3.1 million from commercial banks and those in the securities and investment industry.

OpenSecrets further warns that only about 64 percent of total campaign and PAC contributions are actually identified and sorted by the industry they came from.

CBS News' Hannah Fraser-Chanpong contributed to this report.