The health care worker would be the first Republican to represent District 13 in decades, but Velazquez has not conceded the race yet.
With about 99% of the votes tallied late Tuesday night, Marmorato held a 6% lead over Velazquez who lost heavily in the Throggs Neck area.
Marmorato ran against a new housing development in the mostly low-rise district that became a flashpoint in the race.
Velazquez had a change of heart on her public stance against the proposed Bruckner Boulevard rezoning last October when she ultimately urged fellow lawmakers to approve the project.
The controversial plan would bring more than 300 apartments to Bruckner Boulevard. It's a plan many in the Throggs Neck community vigorously opposed.
Marmorato's victory giving Republicans another seat in the Council may not grow the party's overall numbers by much, but she says it gives her constituents a voice - one that she felt she didn't have on two big issues.
The first one was a proposal to house former inmates with medical needs steps away from her home and the second was the Bruckner upzoning that voters feel strongly about to this day.
"It was at that point that I started to see where leadership's values were aligned and I started to see where my community and my neighbors values were and I felt OK, somebody has to step up here, I'm in health care, I advocate for my patients, so of course I want to advocate for my family and my community," Marmorato said.
Voters in the community said they were really upset so it is a major victory.
"I think it says people are more open to voting across party lines, I think it says that people will look at issues and study issues and I think that people are worried about quality of life," said former City Councilman James Vacca.
One of those issues that Marmorato said will be on her agenda in District 13 in public safety.
Velazquez's campaign did not respond to a request for comment on the upset.
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