The survey, conducted by Farleigh Dickinson University, gives Booker the support of half the registered voters polled, while 22 percent support Lonegan.
That tracks closely with other polls of the race, which have shown Booker up with solid double-digit leads.
He's the heavy favorite to win in October, due to the blue tint of the state and Lonegan's penchant for off-color statements. Most recently, he characterized Booker's comments dismissing speculation over his sexuality as "weird."
In the gubernatorial race, Gov. Chris Christie (R ) leads Democrat Barbara Buono with a similar margin.
The survey was conducted among 700 registered voters Aug. 21-27 and has a margin of error of plus or minus 3.7 percentage points.