Companies including Bank of America and Wells Fargo have contributed $20 million toward the cost of the Democratic National Convention, helping finance an event that Democrats initially said wouldn’t accept corporate money, according to two people familiar with the matter.

Organizers of this year’s convention in Charlotte, N.C., turned to corporations after the city’s host committee struggled to reach its $36.7 million fundraising goal, according to the people, who requested anonymity.

Last year, the Charlotte host committee set up a separate entity called New American City Inc., to take corporate cash and to which Bank of America and Wells Fargo contributed, according to the people. The two banks were on a list of corporate donors released Sept. 1 by the host committee that also named AT&T, US Airways Group, Duke Energy and the law-and- lobbying firm McGuireWoods.

After saying in February 2011 they wouldn’t take corporate money, Democratic Party leaders and convention organizers have grappled with how to cover the estimated $52 million cost of the event, which will end Thursday in President Obama’s renomination acceptance speech.

Duke Energy Chief Executive Officer Jim Rogers, co-chairman of the host committee, “has said that he secured $10 million to $11 million from local corporations from Charlotte,” said Tom Williams, a spokesman for Duke. “He has been working hard to build on those numbers to bring in money” for the convention, Williams said.

“We hit our fundraising target and have the resources we need to host a successful convention,” said Kristie Greco, a spokeswoman for the Democratic National Convention Committee.

Suzi Emmerling, a host committee spokeswoman, didn’t respond to a request for comment. Larry DiRita, a spokesman for Charlotte-based Bank of America, declined to comment, while a Wells Fargo representative didn’t immediately respond to requests for comment.

Party officials met to discuss the convention’s budget on Sept. 1, three days before official programming began, in an indication of how cash-strapped the three-day event is, according to one of the people, who spoke on condition of anonymity.

One way to cut costs, said the people, would be to switch the final night’s event from Bank of America Stadium to the Time Warner Cable arena, where the first two nights’ events will be held. The arena is an alternate site for the acceptance speech in case of inclement weather. The Obama campaign has insisted that possible severe weather won’t force them to move.