Three New Jersey Democrats running in a special U.S. Senate election got their first crack Monday night at the front runner, Newark Mayor Cory Booker, in the first debate among all four candidates in the abbreviated campaign.

(L-R) Cory Booker, Rush Holt, Sheila Oliver and Frank Pallone at Montclair University for special Senate election debate (NJTV via YouTube)

At times, they tried to gang up on Booker to show he's less liberal than them on issues such as using public money to send children to private schools or revising health insurance laws even further.

But largely, the four candidates found themselves in agreement and their differences were relatively nuanced.

The four are running in a hastily scheduled Aug. 13 primary to face a Republican in an Oct. 16 general election in a state that hasn't elected a Republican to the U.S. Senate in 40 years. The winner will serve the last 15 months of the term of the late Sen. Frank Lautenberg, who died in June at age 89.

The special election date itself was political with Democrats challenging GOP Gov. Chris Christie's decision not to schedule it on the same day as the November general election. A court ruled in Christie's favor.

Despite having just six days from the time Christie declared the election dates to enter the race, Democrats with impressive political resumes jumped in.

Booker, probably the state's best known Democratic officeholder, trumpeted how Newark has become an economic engine during two terms in office. In a state where residents are pulled to the north by New York City and to the south by Philadelphia, Booker is the rare politician for statewide office who is known throughout New Jersey.

His candidacy has attracted attention from celebrity Oprah Winfrey, who appeared at a campaign fundraiser last week while Booker's opponents held a debate without him.

"If you like what you're getting from Washington," he said, referring to the two members of Congress in the race, "stick with it."

Assembly Speaker Sheila Oliver blasted Congress as a boys' club and faulted it for helping create China as a place with labor, trade and human rights practices that many in the U.S. find objectionable.

U.S. Rep. Frank Pallone boasted about his helping write the Affordable Care Act, President Barack Obama's overhaul of the health insurance system, calling it the greatest achievement of his time in federal office.

U.S. Rep. Rush Holt, a physicist before becoming a politician, praised the health care law, but argued that it didn't go far enough in a moment that demonstrated some of the starkest differences among the candidates. The contrast was less about what the candidates would prefer than whether it's feasible.

Holt called for a single-payer system where doctors and other care providers would bill the government. Oliver and Pallone both said they endorse that system, too, but don't believe it could get passed in Congress at this point.

"I am totally embracing the Affordable Care Act because I know there are 1.3 million people in this state who have no access to health care," she said, saying that the overhaul will change the status quo.

"A universal single-payer system is not pie in the sky," Holt said, objecting to what he called "the idea that we can't do what's best for America because the tea party toeholds us back."

Booker stressed finding cost savings in the medical system and sidestepped the debate about whether a more drastic government-run approach is possible. He also defended his support of vouchers for students to attend private schools, something both congressmen criticized.

The four candidates are scheduled to meet in a second debate Thursday.

The winner in next week's primary will face a conservative Republican, either former Bogota Mayor Steve Lonegan or Franklin Township physician Alieta Eck.

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