Ten days after residents of New Jersey's 12th Congressional District cast their ballots, Democrat incumbent Rush Holt declared himself the winner Friday on the strength of a 481-vote lead.
Holt's challenger — former Republican Congressman Dick Zimmer — refused to concede the race Friday after requesting a vote recount Thursday on grounds of alleged voting irregularities.
The Zimmer campaign also alleged that the Holt campaign distributed ballots to patients at a psychiatric hospital and modified approximately 400 ballots. A state appeals court ruled in May that it is legal for psychiatric patients to vote following a challenge by the Mercer County Republican Committee in November 1998.
In his speech Friday, Holt — former assistant director of the Princeton Plasma Physics Laboratory — said he was dismayed by the allegations and the actions taken by the Zimmer campaign since Election Day.
Though 500 ballots remain outstanding in largely Democratic Mercer County, both sides agree that the outcome in that county will not favor Zimmer.
The Zimmer campaign has said it will stand by the results of the recount — a process that normally takes two days. Zimmer can, however, request an investigation by the U.S. House of Representatives.
Last week, the Zimmer campaign mounted a failed legal battle to discard approximately 100 provisional ballots — which are ballots for voters who change their addresses 30 days before Election Day.
A panel of appellate judges denied the Zimmer campaign's request to dismiss 74 provisional ballots from Mercer County alone. The Zimmer campaign contested that affidavits certifying voters' addresses — which should have been filled out ahead of time — were either placed inside the ballots or stapled to the front.
The Mercer County provisional votes may have been among the 932 total votes cast at the Trinity Church and Jadwin Physics building polling locations.
"There are some [provisional ballots] in both [Princeton] Borough and the Township that the the Superintendent's office has recommended the Board of Elections not to accept, but the count is not final," Betty Monroe — deputy election supervisor in Mercer County — said Wednesday.
Since Election Day, the race has remained too close to call as the lead changed from a 731-vote margin in Zimmer's favor on election night to a 56-vote Holt margin the following day. Neither candidate conceded or declared victory as Holt and Zimmer waited for the results of the provisional ballots.
If Holt maintains his lead through the recount this week, the Democrats will have a one seat lead in New Jersey's House of Representatives delegation, and will close the Republican lead in the House to seven seats, with the Republicans holding 220 seats to the Democrats' 213.

(The Associated Press contributed to this report.)