NEW YORK — Eliot Spitzer's 11th-hour comeback campaign isn't just a race to the finish. It's a sprint to the start.

After plunging into the city comptroller's race Monday, the scandal-scarred ex-governor has until midnight Thursday to collect 3,750 valid petition signatures to get on the Democratic primary ballot for September.

"The number is big," Spitzer said Wednesday outside a Manhattan bar where his campaign was holding a petition-signing party for supporters. "Three thousand seven hundred and fifty is a significant number of petitions to gather in three days."

Still, he said he felt confident his campaign would collect enough signatures by the deadline, but he refused to say how many more he needed.

Spitzer got encouraging news from the first poll taken since he became a candidate. He topped fellow Democratic hopeful Scott Stringer by 42 percent to 33 percent among registered Democrats, according to a Wall Street Journal-NBC 4 New York-Marist survey, which questioned 546 people and had a margin of error of 4.2 percentage points.

Spitzer said that while the poll numbers were "comforting" he was aware he had more work to do.

"I'm never confident," he said. "And that is defensive politics."

Stringer campaign manager Sascha Owen expressed confidence that Stringer, the Manhattan borough president, would prevail as more voters get to know him.

Two-thirds of the Democrats surveyed said Spitzer, who resigned after being identified as a client of a pricey escort service that was under federal investigation, deserves a second shot at politics.

Getting the petition signatures to get there will be a formidable task in such a narrow timeframe, experts say.

"That's the real challenge, the four days," said Jerry Skurnik, a longtime New York Democratic consultant who isn't working with Spitzer. "It could be done, if they spend enough money and they're really organized."

Spitzer moved quickly on getting signatures after announcing his surprise decision to seek New York City's top financial office. His self-financed campaign on Monday posted an online ad offering canvassers $12 an hour to gather signatures.

The process can be painstaking. In Spitzer's case, signers need to be registered Democrats who live in the city and haven't signed another comptroller hopeful's petition. Signers must supply their names and addresses and date the forms, and signature-gatherers also have to fill out certain information.

City candidates were allowed to start petitioning in early June, and many did. Campaigns generally gather two to three times as many signatures as needed, in case some are challenged as having incomplete addresses, missing dates, signers who aren't registered Democrats or other flaws.

Some candidates submit many extra signatures as a show of strength. Stringer has garnered upward of 100,000 signatures through an all-volunteer effort, his campaign said.

"I know the circus is in town, but we're going to make this a very short run. ... I'm ready to go," Stringer said Wednesday on MSBNC's "Morning Joe."

Spitzer has said he's aiming for 7,500 signatures. He picked up several Monday as he made his way through a Manhattan park, encircled by reporters.

Spitzer is trying to stress how he'd use his experience to create a more muscular comptroller's office. As attorney general before his time as governor, he became known for going after fraud, self-dealing and shady practices on Wall Street.

But he hasn't quieted criticism about the call girl scandal.

Two women's rights group leaders held a news conference Wednesday to denounce his candidacy.

"Why would you vote for the guy who used women as objects" and threw the state into turmoil when the allegations came to light, asked Sonia Ossorio, the president of the National Organization for Women's New York City chapter.

And Spitzer faced continued questions in TV interviews about his conduct in office and after.

"It was alleged, and I did not deny, and I faced up to the allegation, acknowledged it — I had participated in seeing prostitutes. ... I tried as best as I could in the context of that moment to hold myself accountable by resigning," he said Tuesday night on "The Charlie Rose Show," which airs on PBS stations.

Spitzer was never charged with any crime. Asked on Tuesday night's show and on CNBC's "Squawk Box" on Wednesday whether he had patronized prostitutes since his resignation, he said he hadn't.

Other comptroller contenders include Republican John Burnett, who has worked on Wall Street; Green Party candidate Julia Willebrand, a former teacher; and Libertarian Kristin Davis, a former madam.