TRENTON, N.J. — Aides to U.S. Senate candidate Steve Lonegan in New Jersey have taken down a social media post that Newark Mayor Cory Booker's campaign says was offensive.

Lonegan is the GOP front-runner in the Senate primary Tuesday. Booker is the Democratic front-runner. A special election in October will fill the seat left vacant when Sen. Frank Lautenberg died this summer.

A tweet Thursday by the Lonegan campaign said: "Just leaked — Cory Booker's foreign policy debate prep notes." It showed a map labeling parts of Newark "West Africa, Guyana, Portugal, Brazil" and other nations including Afghanistan and Pakistan.

Newark is a largely minority city whose residents have roots in many parts of the world.

Booker's campaign manager called the posting "inappropriate, offensive and fundamentally out of step with New Jersey values."

"We need leaders who will lift up our communities, not tear them down," Booker campaign manager Addisu Demissiehe said in a statement.

Lonegan aide Rick Shaftan said the post, which also appeared on the campaign's Facebook page, was taken down at Lonegan's request when he became aware of it Thursday night — before any Democrats complained about it.

Shaftan said he got a call from Lonegan, who was at a fundraiser, on Thursday night. Shaftan said the candidate told him, "This isn't funny, when did this happen? Get this down immediately."

He said it was put up by another campaign staffer, who remains with the campaign.

"The person who put it up isn't going to do it again," Shaftan said. "They're not going to make that mistake in their life again ever."

The post also drew criticism from Shavar Jeffries, who is running for mayor of Newark in 2014. He issued a statement Friday, saying removing the post "is a poor substitute for an apology."