The two attacked each other's positions on issues ranging from the government shutdown to abortion in a lively one-hour debate, seen on WABC-TV, ahead of the Oct. 16 special election to fill the remaining 15 months of the late Sen. Frank Lautenberg's term.
The fireworks began out of the gate as Lonegan, 57, ripped Booker's record as mayor of Newark, citing a rise in violence and unemployment in the city.
"We simply cannot allow Cory Booker, 44, to bring his failed record as mayor of Newark to the U.S. Senate," the former Bogota mayor said. "We need a leader, not a tweeter."
Booker has more than a million Twitter followers.
He fired back that Lonegan is attacking to try to "distract from his extremist views," invoking Lonegan's association with what he called the "Tea Party fringe" throughout the debate, a group he blamed for "hijacking" the federal government over implementation of the new federal health care law. Lonegan is the former state director of Americans for Prosperity, a conservative political advocacy group founded by the billionaire Koch Brothers.
Booker said Newark is enjoying major growth, citing new businesses coming to the city and the building of new high-rises, but Lonegan countered that the only person enjoying economic growth in Newark is Booker.
"Mayor, you've made your entire fortune as the mayor of Newark," he said. "You've made a six-digit salaries as mayor of Newark and going around the country speaking."
Booker said he is transparent about his financials, pointing out that he has released 15 years of tax returns, while Lonegan has not.
"If you listen to his rhetoric, it seems obvious that if he goes down to Washington, he'll make what's wrong with Washington worse," said Booker.
Gov. Chris Christie endorsed fellow Republican Lonegan, but it was Booker who dropped the governor's name when asked who he's compromised with politically. Booker said he and Christie found common ground on education and have managed to improve Newark schools by working together.
Booker and Lonegan also sparred over abortion, raising the minimum wage and legalizing same-sex marriage (Booker supports all three while Lonegan is opposed), but they managed to find common ground on government spying (both opposed) and the need to revamp the post-9/11 Patriot Act, which both support.
The race has produced some theatrical moments, such as when Lonegan rolled out a red carpet at a restaurant to mock Booker's appearance at a fundraiser in California with Matt Damon and Ben Affleck. Or when he held a news conference in front of two derelict Newark properties once owned by Booker and since donated to charity. Or when he stood outside the New York headquarters of Waywire, Booker's social media startup, to call attention to his opponent's relationship to Silicon Valley investors.
Booker, who is better known than Lonegan and has raised a lot more money, has mostly stayed above the fray. But he also hasn't been available much to answer questions about the accusations Lonegan has levied.
The special election to fill the remaining 15 months of the late Sen. Frank Lautenberg's term will be Oct. 16.
WATCH THE DEBATE:
Some information from The Associated Press