J. Shelby Bryan, the long-term boyfriend of US Vogue editor-in-chief Anna Wintour, owes the US government more than $1.2 million (£760,000) in taxes.
Mr Bryan, a former adviser to Bill Clinton who helped raise funds for Mr Obama's re-election campaign, has owed the money to the Internal Revenue Service (IRS) since 2006, according to court filings obtained by The Daily Telegraph from Texas.
Mr Bryan, who has been in a relationship with Ms Wintour since 1999, was also pursued for outstanding Texas property taxes, and has had energy companies he owns in the state chided by local authorities for falling behind on their financial filings.
The findings may threaten Ms Wintour's confirmation as a US ambassador if nominated by Mr Obama. Her appointment would need to be approved by the US Senate, which has in the past objected to irregularities in the tax affairs of nominees and their partners.
Mr Bryan, 66, was said to have a fortune of $30 million when he left his second wife, Katherine, for Ms Wintour 13 years ago. He reportedly suffered a decline in personal wealth amid the financial crisis, however, and frequently stays at Ms Wintour's $10 million townhouse in Manhattan.
Ms Wintour was one of Mr Obama's leading fundraisers during his re-election campaign, bringing in $500,000 to the president's coffers. At one $35,000-a-plate fundraising dinner in August, Mr Obama thanked "Anna and Shelby for being such extraordinary hosts".
While helping to add to Mr Obama's $1 billion re-election fund, however, Mr Bryan had a significant debt to the US government. A lien filed in Texas shows that he owed more than $1.6 million in March 2006. He has since paid back about $400,000.
Mr Bryan said in an interview with The Daily Telegraph that he received the tax bill after "unravelling" a stockholding arrangement that was previously used as a loophole by investors to delay paying tax, before it was banned by US authorities in 1997.
"I had a thing that you will never want to happen in your life," he said.
"It was a situation that created tax liability but no cash". He said that he had drawn up a repayment programme with the IRS, which had been "very accommodating", and that he was "on schedule".
Asked why he had not acted to clear the entire tax bill immediately, Mr Bryan said: "I would have loved to have done that – if I had the cash I could have".
Records also show that in 2010 Mr Bryan was pursued for about $20,000 in overdue property taxes by authorities in Harris County, Texas. He blamed "a series of perfect storms" that struck after he replaced his accountant with another who died, and who was replaced by another "who was not adequate".
"I've paid Harris County so much money in so many taxes, and that's the only time it went awry," he said. "I mean it was my fault, you know people in the office weren't doing their job – but it was kind of an exceptional situation." He later paid the bill in full.
Mr Bryan blamed the same office confusion for corporate records in the state also showing that a string of his energy companies had their corporate registrations revoked. He said a staff member who "just didn't know better" had failed to notify authorities that he was winding down some of the firms.
Mr Bryan continues to lead several energy and financial companies. He also serves as a director to a Virginia-based communications firm, which sells voice-over-internet services to businesses.
He owns a three-bedroom condominium valued at $720,000 in Houston, Texas, and sold a second Houston apartment for about $150,000 in June last year.
However he is frequently seen in New York with Ms Wintour, the editor-in-chief of Vogue magazine, whom he accompanied to the White House for the state dinner in honour of David Cameron during the prime minister's visit to Washington last year.
A descendant of the Austins, one of Texas's oldest families, Mr Bryan went from being a young banker to making his fortune as one of the earliest investors in the burgeoning US mobile phone industry from the mid-1980s.
Having been one of Mr Clinton's most loyal and lucrative fundraisers during the then-president's re-election campaign in 1996, he was appointed to Mr Clinton's Foreign Intelligence Advisory Board.
More From Business Insider