WASHINGTON -- Donald Trump, who spent more of his own money on his campaign than any other presidential candidate in history, also raised more in small-dollar donations than anyone else ever did.

Trump brought in $239 million in donations of $200 or less, more than Democrats Hillary Clinton and Bernie Sanders combined, according to the Campaign Finance Institute, a Washington-based research group.

He also proved more adept at raking in small-dollar contributions than Barack Obama, who brought in $219 million in 2012 and $189 million in 2008. Clinton raised $137 million and Sanders $100 million in donations of $200 or less.

More than two-thirds of Trump's donations, 69 percent, were in small amounts, compared with 44 percent for Sanders and 22 percent for Clinton.

The contributions were raised by both Trump's campaign committee and his joint fundraising effort with the Republican National Committee.

While Trump was running, his campaign said small dollar donors showed how much strength the candidate had with rank-and-file voters.

"... it shows how Mr. Trump's message is resonating with millions of voters across the country," Trump's digital director, Brad Parscale, said in the statement a week before the election, when the campaign announced it had surpassed $100 million in smaller donations.

On the other end of the scale, 72 percent of Gov. Chris Christie's presidential campaign contributions were the maximum $2,700, third highest among all of the 2016 presidential candidates.

Former Louisiana Gov. Bobby Jindal raised 75 percent of his money from donors who gave the maximum, followed by former Florida Gov. Jeb Bush with 74 percent.

Trump raised just 9 percent from donors who gave $2,700; Clinton, 35 percent. Trump also contributed $66.1 million from his own pocket.

The president did raise money from special interests, even as he vowed to "drain the swamp in Washington" and attacked his challengers as being beholden to their campaign contributors.

Trump's two biggest outside sources of campaign cash were employees from two coal companies, Murray Energy and Alliance Resource Partners, according to the Washington-based Center for Responsive Politics, which tracks campaign giving. Trump signed legislation that removed restrictions on coal companies dumping mining waste into waterways.

His next two biggest corporate sources of contributions were employees of Bank of America and Wells Fargo. Trump has pledged to roll back the financial regulations enacted in response to Wall Street practices that helped cause the Great Recession.

Jonathan D. Salant may be reached at jsalant@njadvancemedia.com. Follow him on Twitter @JDSalant. Find NJ.com Politics on Facebook