Failed U.S. Senate candidate Christine O'Donnell denies she inappropriately used campaign funds.
O'Donnell tells ABC's "Good Morning America" that the allegations against her are a "thug politic tactic."
The Delaware Republican appeared on several network morning shows after it was revealed that federal authorities have launched a probe to determine whether she broke the law by using campaign money to pay personal expenses.
O'Donnell says neither she nor her campaign have been informed of a federal investigation.
She suggests the accusations are being driven by her political opponents on the right and left, including Vice President Joe Biden.
O'Donnell was the tea party favorite who scored a surprise primary victory this year only to lose badly in the November general election.
She set a Delaware state record by raising more than $7.3 million in this year's campaign, and has been dogged by questions about her personal and campaign finances.
At least two former campaign workers claim that O'Donnell routinely used political contributions to pay personal expenses including her rent as she ran for the Senate three consecutive times, starting in 2006.
She acknowledged in a newspaper interview in March that she paid part of her rent with campaign money, arguing that her house doubled as a campaign headquarters.