In New Jersey's only congressional race Tuesday that stood a chance of dethroning an incumbent, Democratic challenger Josh Gottheimer declared victory over Rep. Scott Garrett, quashing the Republican's quest for an eighth term.

But more than 20,000 mail-in ballots remain uncounted  with a current vote gap of about 10,000, meaning the race can still be considered too close to call.

When reached for comment, Garrett's camp would not concede the race even as Gottheimer claimed victory.

"The outcome of this race should not be called until these ballots can be counted," Garrett said in an emailed statement. "Election officials expect that the absentee ballots will not be tallied tonight."

Garrett also said that a large number of provisional ballots may not be verified and counted for several days.

"I stand before you tonight honored to be the next congressman for the 5th Congressional District," Gottheimer told a rowdy crowd in Hasbrouck Heights shortly after midnight.

Gottheimer, a former Microsoft executive and Democratic speechwriter, secured a much-needed landslide victory in Bergen County. The rest of the district covering parts of Bergen, Passaic and Warren counties is overwhelmingly Republican.

"They said this couldn't happen, that our district was just too partisan, too entrenched, that the ads would be too expensive, and the odds would be too long," Gottheimer exclaimed. "All of you proved them wrong."

Garrett had beaten back Democratic challenges before. But Gottheimer fundraising total edged Garrett's by $500,000.

Garrett, considered the state's most conservative congressman, took heat this year for saying that his party should not support openly gay candidates.

Gottheimer also attacked Garrett’s votes against the Zadroga Act, a federal law providing health care for 9/11 responders. The bill was named after North Arlington resident James Zadroga, an NYPD officer who responded to Ground Zero and died in 2006 at age 34 with a respiratory illness. Garrett, however, did vote for the bill that eventually was signed into law.

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Sergio Bichao contributed to this report.

Contact reporter Dino Flammia at dino.flammia@townsquaremedia.com.

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