The Post analysis shows that, among the approximately 420 organizations that paid Bill Clinton to speak during those years, 67 were also foundation donors that each gave the charity at least $10,000.

Many of those funders were major financial institutions that are viewed suspiciously by liberals whom Clinton has been courting as she seeks to secure the Democratic nomination — and avoid a vigorous primary challenge from the populist left.

Four major financial firms — Goldman Sachs, Barclays Capital, Deutsche Bank and Citigroup — collectively have given between $2.75 million and $11.5 million to the charity, which is now called the Bill, Hillary and Chelsea Clinton Foundation. Between 2001 and 2013, their combined speech payments to Bill Clinton came to more than $3 million.

The Post analysis also revealed aspects of Bill Clinton’s paid speaking career during Hillary Clinton’s tenure at the State Department that were not clear from her public filings.