Maybe the idea to build a pedestrian bridge from Jersey City to Manhattan is a far-fetched one. Maybe.

But it's one Jersey City Mayor Steven Fulop likes a lot.

"Every great infrastructure project starts with a vision and a concept people say will never happen," Fulop told New Jersey 101.5. "Once it gets built, everyone tries to take credit for it."

Fulop is one of the more than 1,600 people who, as of Friday, has signed a petition in support of the "Liberty Bridge," a proposed 5,000-foot walkway supporters hope would alleviate congestion on PATH trains and other avenues to and from New York City.

So far, the plan is just a few renderings and an idea that's been kicked around by the Jersey City residents behind it — there have been no meetings, no applications, no cost estimates.

What there has been, though, is momentum. By Friday, the petition had twice as many "signatures" as a day earlier.

"It's got to start somewhere," said Kevin Shane, who's worked with architect Jeff Jordan to conceive of the idea and begin promoting it through social media. "It needs to get the support of the neighbors and the cities and the state, of course. But for me to have a valid push to the next step, to talk to the government more formally, we needed to show people are on board."

Shane said he's had just the earliest conversations about costs. He knows any formal proposal would involve a lengthy, rigorous, bureaucratic process, involving not just the governments of New York City and Jersey City, but New York State, New Jersey and the Port Authorty.

Fulop sees potential for making it happen if the idea piggybacks along with the rail tunnel Govs. Chris Christie and Andrew Cuomo have asked the federal government to help fund. That idea, not quite in the infancy of the pedestrian bridge project, isn't particularly far along — the federal government hasn't committed to any help.

"The hope is that with the collective voice of the thousands of people who sign the petition, once the tunnel does get build, everyone would agree this is a necessity," Fulop said.

Dollars are scarce, the mayor said, but incorporating pedestrian access into a broader plan could make a lot of sense, he said.

"I think the most significant thing that can happen right now is that people sign the petition," he said.

Shane said he's encouraged by the support so far — and thinks commuter congestion is reaching a point where the government could be convinced a pedestrian walkway could help.

"Jersey City's got this great hype, and it's getting more and more desirable — and it's also getting more crowded," he said. "I've got to start somewhere."

Louis C. Hochman is digital managing editor for NJ1015.com. Reach him at louis.hochman@townsquaremedia.com or on Twitter @LouisCHochman.