The results of one major congressional primary are still up in the air more than a month after Election Day.

In their Democratic primary, Congresswoman Carolyn Maloney clung to just a 648 machine-vote lead over lawyer Suraj Patel, but she’s been confident she’d widen that margin as absentee votes are counted.

Now, as the Board of Elections shuffles through the ballots in Manhattan, it appears she’s pulling further and further ahead.

"The margin is now between three and four times what it was on Election Day," said Maloney campaign spokeswoman Rachel Brody. "And we are still counting some of our best areas. So, at this point, the math is on our side."

Maloney, in office since 1993, was traveling to Washington Friday for votes.

Figures obtained by NY1 from the Upper East Side Assembly district considered a Maloney stronghold showed she leads there by nearly 3,000 absentee votes.

She made gains elsewhere in the borough, too.

This is the second time she’s faced Patel as a challenger.

But his campaign said he’s not ready to concede.

"As of right now, we are fighting to make sure every ballot is counted, every voice is heard," said Patel campaign spokeswoman Cassie Moreno. "We are one of the biggest Democratic cities in the country. We should be setting the bar on voter enfranchisement."

The 12th Congressional District had the most absentee ballots returned of any House district in the city. It had 65,700 absentee votes returned compared to 39,600 in-person votes cast.

But the district also has steep rates of ballot invalidation. Its Manhattan and Queens portions saw 19 percent of absentee votes preliminarily tossed. Its Brooklyn portion? Twenty-eight percent.

A chief reason for invalidated ballots is the voter’s failure to sign the envelope.

Patel has noted that 12,500 ballots were tossed in his district.

"I will be at the forefront of fighting for November’s ballot envelopes to be much more clear with a box that says if you do not sign here, your vote will not count," Patel said. "It’s that simple. And how New York has these, one in four people are not going to have their votes counted. Imagine that. The trust in the electoral system would fade away."

Patel is a plaintiff in a lawsuit against the state over ballots that were invalidated because they weren’t postmarked — an offense that is not the fault of the voter.