Rep. Charles Rangel's (D-N.Y.) primary rival on Friday filed a legal challenge to the ballot-counting process as the 82-year old lawmaker's margin of victory in Tuesday's Democratic primary narrowed.

Rangel seemingly won Tuesday's competitive primary against state Assemblyman Adriano Espaillat. The former House Ways and Means Committee chairman declared victory and Espaillat conceded defeat.

But since then, as ballots have continued to be counted, Rangel's reported margin of vicotroy has shrunk from 6 points on Tuesday, when reports gave him a 46 percent to 38 edge with 82 percent of precincts reporting, to 2.6 percent, media reports said.

Espaillat’s campaign has raised the stakes, charging that the state election board has not allowed their campaign to "adequately monitor" the counting of votes.

"Three days after a winner was declared in this election, there are still votes to be counted," Espaillat's campaign said, calling for an open process, according to reports.

According to a report in the Wall Street Journal, only 1,032 votes separate the two men out of the 38,506 total which were cast, with 70 election districts still uncounted.

Reports say vote totals from six percent of precincts were still missing from the reported tallies.

While Rangel’s margin has shrunk and both campaigns are closely watching the count, Espaillat, has yet to retract his concession and there is still no certainty that Rangel's supposed victory will be undone. 

“We're waiting for the results of the Board of Elections," said Moises Perez, Rangel's campaign manager, according to reports. "It's a process that has to be completed by them. We want them to do it as soon as possible."

The primary fight was the toughest of Rangel's 42 year career in Congress. The veteran lawmaker had been hit by an ethics scandal which led to him being stripped of much of his power and culminated in a rare House censure in 2010. 

He was also forced to run in a redrawn district that was now Hispanic-majority for the first time, boosting the prospects of his rival, the Dominican Republic-born Espaillat.