As her political star began to rise, public documents show, so too did a string of financial issues.
In March, the IRS initiated an audit and placed a lien against her for $11,744.59 in taxes and penalties from the 2005 tax year.
"They made up an accusation about an IRS tax lien," O'Donnell said Wednesday on "Good Morning America," hours after winning the primary. "The IRS said it was a mistake. They cleared it up right away. We gave my opponent and the Republican administration, showing them that the IRS had admitted to a computer error. They chose to ignore the truth because they don't have a record to stand on."
Since 1994, Farleigh Dickinson University in New Jersey has sued O'Donnell five times for outstanding debts of about $5,000.
O'Donnell claimed to have graduated from the school 17 years ago -- and claimed to have a degree during her 2006 Senate campaign -- but the school said she did not officially graduate until two weeks ago.
In previous interviews, O'Donnell said the school withheld the diploma because of the money. But a school official interviewed by Politco.com said the degree was not conferred because she had not completed her coursework.
"It took me 12 years to pay off my college loans," she told "GMA." "I'm not a trust fund baby. Most Delawareans can relate to having to work hard to pay for their own college education. I was never dishonest about that."
In a March interview with Delaware's News Journal, O'Donnell admitted to living in a three-bedroom home with David Hust, a campaign staffer and Christian rock musician, and paying half her rent -- between $1,645 and $2,020 a month -- with campaign donations because she used the home as a campaign office, as well.
"I am renting from the campaign," she told the paper. "I'm an unconventional candidate because I believe that we have to make sacrifices."
O'Donnell, who previously owned a home, also was sued by her mortgage holder in March 2008 at the height of her campaign against then-Sen. Joe Biden.
The company secured a mortgage default against her for $90,421 and the house was to be foreclosed and sold at auction. Instead, O'Donnell told the News Journal, she sold the house to a campaign lawyer. She said she intended to buy the house back, but decided instead to run again.
When asked on "Good Morning America" about her financial past, O'Donnell said, "We've addressed all of this stuff on our website."
Anyone looking for that information on the site this week, however, would be unable to find it.
Visitors to christine2010.com were given just one option when they visited the site Wednesday, the chance to donate money. No other pages or information were available on the site except for the link allowing one to donate to the campaign.
A goal of raising $50,000 on the site was updated later in the day to $750,000.
Calls to the campaign from ABCNews.com seeking further comment were not returned.
ABC News' Ray Sanchez contributed to this report.