Newark Mayor Cory Booker is poised to win big on Tuesday in the New Jersey Senate Democratic primary — but all eyes will be on his victory margin.

The most recent poll from Quinnipiac University showed the mayor with a 37-point lead, and anything but a significant double-digit victory, in the high teens or greater, over Reps. Rush Holt (D) and Frank Pallone Jr. (D) will be seen as a disappointment dimming Booker’s rising star.

It may also be seen as a sign that Booker’s victory in the fall isn’t as inevitable as originally thought.

Booker’s star has lost a bit of luster in recent weeks from a report that he received payments from his former law firm after resigning to serve as Newark’s mayor and one outlining his close ties to the tech industry.

The two House members argue little stock should be put in the polls since New Jersey has never seen an August primary. Turnout is expected to be as 190,000 to 300,000 voters — with many New Jerseyans expected to vacation at the shore rather than hit the polls.

But Patrick Murray, director of the Monmouth University Polling institute, said the negative news stories about Booker have emerged too late to make a difference in the primary.

“There wasn't enough time for Booker's primary opponents to do anything about the reports, and he's expected to win with a large margin on primary day,” Murray said.

To be sure, Booker will be a heavy favorite over Republican Steve Lonegan.

Still, Murray said the GOP challenger at least has more time to make his case against Booker, and a smaller margin on Tuesday could suggest some vulnerabilities.

“If Cory Booker wins by a much smaller amount than we anticipated, maybe his support isn’t as deep,” Murray said.

Lonegan said he believes the recent negative news stories about Booker will play in the general election.

“The reports are very deeply disturbing to a lot of people. Some of the biggest companies in the country have pretty much bought off Cory Booker,” he said.

Lonegan is referring to reports that Booker’s stake in a tech startup and donations from Silicon Valley shows he is beholden to the tech industry. Separately, the New York Post reported Booker continued to receive payments from his former law firm after resigning to serve as Newark’s mayor. That firm received $2 million in fees from various local agencies over which Booker had some influence.

Booker’s considerable name recognition and star power gave him an edge in the abbreviated primary and will also help him against Lonegan.

Oprah Winfrey held a fundraiser for Booker, while Eva Longoria appeared at a primary eve rally for him on Monday night, and Hip-Hop star Q-Tip of the group A Tribe Called Quest will DJ at Booker's election-night rally.

Democrats got in very few knocks on Booker in the primary, in part because they hoped to avoid significantly damaging him for the general election.

Still, Holt told The Hill “cracks” are beginning to show in Booker's candidacy.

“He has a well-crafted story of inevitability, and that's beginning to crack. I wouldn't say shatter, but it certainly is showing some cracks,” he said.

Lonegan faces more problems in the fall.

He’s going to be outspent: Lonegan had just over $150,000 cash on hand at the end of July and will face a multi-million dollar campaign from Booker.

Conservative political action committees could get involved, but a number of outside groups privately acknowledged that, even if Booker is weaker than shown in initial polling of the race, they’d be unlikely to invest in a race where the fundamentals are stacked against Republicans.

New Jersey hasn’t sent a Republican to the Senate in 41 years, and Lonegan is considered too conservative and too much of a bomb-thrower to make the race particularly competitive.

New Jersey Gov. Chris Christie (R) has said he’ll endorse whomever wins the GOP nomination — and Lonegan told the Hill he hopes Christie will campaign with him. But there’s little indication the governor will jeopardize his own reelection bid by sticking his neck out for a former primary opponent.

Booker may face some dissension within his own party, having created some bad blood among other Democrats by announcing his Senate bid before Sen. Frank Lautenberg (D-N.J.) had indicated whether he planned to retire.

Neither Holt nor state Assembly Speaker Sheila Oliver, another Democratic primary contender, would commit to endorsing the eventual nominee.

Holt declined to speculate on what he would do if he didn’t win the race, though he said he expected Democrats to work together to defeat Lonegan. Asked outright whether he’d endorse the winner, he demurred.

Oliver wouldn’t guarantee she’d work for Booker either.

“In terms of me going all in to support whoever emerges out of the primary, it’s going to depend on what they’re going to commit to in terms of policy,” she said.