Mark Foley, the incumbent was considered likely to win Florida's 16th congressional district election in 2006 but on September 29, 2006 he said he would resign from his office because of a sex scandal.
One poll taken by Hamilton Beattie on September 12, 2006, had Foley leading Tim Mahoney in a matchup by 48% for Foley to 35% for Mahoney .
According to the state of Florida, 42% of the voters in this district are registered Republicans, and 36% are registered Democrats. George W. Bush won this district with 52% of the vote in the 2000 presidential election, and with 54% of the vote in the 2004 presidential election.
Mahoney has sharply criticized the Bush administration for overspending, general mismanagement, and its policies in Iraq. In August, General Wesley Clark endorsed the candidacy of Mahoney for Congress.
On September 28, 2006, ABC News reported that Republican incumbent Mark Foley had sent email messages, from his personal AOL account, to a then-16-year-old former Congressional page, asking the page to send a photo of himself to Foley, among other things that were overtly sexual in nature.
Mahoney has called for a full investigation of Foley's actions. The next day Foley submitted a letter of resignation from Congress on September 29, 2006 in the wake of news reports about the communications.
Republicans' hold on Mark Foley's seat went "from safe to shaky overnight." On October 2, 2006, the Florida Republican Party Executive Board selected state representative Joe Negron as Mahoney's new opponent. However, Negron's name did not appear on the ballot so he only received votes cast for Foley, whose name remained on the ballot by law.
On election day Mahoney narrowly defeated Negron by 1.8 percentage points. While Negron carried most of the more conservative areas of the district near Fort Myers, Mahoney carried the two largest counties in the district, Palm Beach and St. Lucie counties, by a combined margin of over 10,000 votes — far more than the actual margin of victory.
He is the first Democrat to represent the district since its creation in 1973 (it was the 10th District until 1983 and the 12th District until 1993).