Lonegan seized on the new findings, which come as he has aggressively attacked Booker's record on crime, his controversial role in a flagging Internet start-up, and his buyout agreement with a West Orange law firm he worked for before becoming mayor that still receives contracts from the city.
For his part, Booker has largely stayed out of public view since Labor Day.
"My campaign is clearly gaining momentum," Lonegan said. "We have exposed Cory Booker as a Hollywood wannabe with a failed liberal record, and New Jerseyans are embracing the message of limited government and individual liberty."
The Quinnipiac poll, conducted from Thursday through Sunday, surveyed 948 likely voters in the Oct. 16 special election. It has a margin of error of plus or minus 3.2 percentage points.
The Booker campaign was scheduled to make four stops throughout the state Tuesday. But Booker, who spent the weekend attending fund-raisers in California, made no public appearances.
Campaigning in his place Tuesday morning in South Jersey was Massachusetts Gov. Deval Patrick, who implored voters to send Booker to the Senate to help rebuild the "sense of community and common cause" that "has been coming unraveled in this country for a long time."
Patrick joined a growing list of high-profile politicians who have either made endorsements in the race or taken to the campaign trail. Maryland Gov. Martin O'Malley, considered a possible contender for the 2016 Democratic presidential nomination, stumped for Booker during the Democratic primary. U.S. Sen. Rand Paul (R., Ky.) rallied with Lonegan on Sept. 13, and Texas Gov. Rick Perry is also set to endorse Lonegan next week.
Asked by reporters about the Quinnipiac poll, Patrick said, "The one thing good about it is it will make sure that people of good will aren't complacent, and that Democrats don't sit around and say, 'Well, it's in the bag.' We've got to get out and work and earn it."
Patrick dismissed Lonegan as part of a "band of radicals who want to drive the country and its economy over a cliff."
He also bristled at a reporter's question about Booker's absence from the campaign trail. "You know how much it costs to run for U.S. Senate from New Jersey?" he said. "It's a big state, and he is trying to leverage his campaign by having some of his friends come in and help.
"I don't actually vote in New Jersey, but I do care about the business of the U.S. Senate," Patrick told a few dozen seniors at the John F. Kennedy Recreation Center in Willingboro. "And what they do right and what they do wrong affects us at home in Massachusetts as well.
"It seems to me what we need in our political leadership and in our civic leadership is an invitation back to common cause, an invitation back to community," Patrick said. "And leadership that is about asking us to turn to each other instead of on each other. That's why I'm for Cory Booker."