Andy Kim's lead climbed to 4,353 votes Friday in his tight race against incumbent Tom MacArthur in New Jersey's Third District congressional race, up from the 2,622 margin he had when he claimed victory Wednesday night.

The number increased after 1,760 votes that had not been counted on Election Day were added to the tally late Thursday by the Burlington County Clerk's Office. Of those votes, only 29 went to MacArthur.

MacArthur, a Republican, has not conceded and said in a statement Wednesday night that he would wait until all the votes are counted.  In a text Friday night, MacArthur's campaign spokesman  said there would be no comment.

Burlington County officials said they will continue to count 4,800 provisional ballots through the weekend, and Ocean County will meet next week to finish its ballot count.

The Third District includes many towns in Democratic-leaning Burlington County and a large swath of Republican-leaning Ocean County. On election night, it appeared that MacArthur won the district by about 2,000 votes, but there were still thousands of ballots that had not been counted in Burlington County.

The unofficial tally on election night, which showed MacArthur had the edge out of more than 290,000 votes cast, did not include the 26,800 Vote-by-Mail ballots received in Burlington County. When those were counted the next day, Kim, the Democrat, went ahead with the 2,622-vote lead.

Then, on Thursday night, the Burlington County Clerk's Office counted 1,760 more ballots. Poll workers in some districts had failed to deliver machine cartridges containing those ballots to the county's election headquarters on election night, and the machines in question had to be opened by court order on Wednesday night.

Deputy Clerk Wade Hale said it was later discovered that some of those machines were empty and that poll workers had delivered the cartridges in the "wrong bags" instead of the container that was supposed to contain all the cartridges. Another problem was that one cartridge jammed and the back-up vote receipt had to be removed from the machine so the ballots could be counted.

There are still about 7,200 provisional ballots in the district that have to be counted by election officials in Burlington and Ocean Counties, a process that could take days. But there are twice as many provisionals in Democratic-leaning Burlington and the count is not expected to change the outcome, Burlington County officials say.

Burlington County Superintendent of Elections George Kotch said he expects he will have to work through the weekend to finish checking the 4,800 provisional paper ballots against voter registration records to determine which are legitimate. He said voters who were convicted of a felony, who were not properly registered, or who received a vote-by-mail ballot and submitted it would have their provisional ballots disqualified.

Ocean County election officials said that they would not begin counting their provisional ballots — about 2,400 — until Wednesday, when a publicly advertised meeting will be held at 11:30 a.m. at the county courthouse in Toms River. An official said that two Republican election commissioners and two Democratic commissioners will "hand count" those ballots before they can approve the final tally.