TRENTON, N.J. (AP) — New Jersey Gov. Chris Christie is not worried about a lawsuit filed against him by three left-leaning advocacy groups.

Speaking Saturday at the Iowa State Fair, Christie said the groups have repeatedly sued him. The latest litigation "is just another of the pile of garbage" the groups have filed, he said.

The suit accuses the Republican of violating his financial responsibilities to the state. It claims he's forcing taxpayers to cover the cost of his security details' accommodations while he travels the United States campaigning for the GOP presidential nomination.

The suit asks the court to find that actions by Christie and Chris Christie for President Inc. "constitute a wrongful and unprivileged conversion of taxpayer funds" and that they should reimburse the state. They're also taking issue with any role state employees may have played in his campaign launch.

Christie has long argued his campaign shouldn't pay the costs because his state police protection is mandatory regardless of what he's doing.

The New Jersey Working Families Alliance and New Jersey Citizen Action are among the plaintiffs in the suit filed Friday in Mercer County. There are also some individuals listed as plaintiffs.

"It's just another step by liberal advocacy groups in my state who don't like the fact that a conservative governor of New Jersey has been running the state for six years," Christie said. "They've sued me over so many things, it's hard to keep track. This is just another of the pile of garbage that they put a title on and file with a check at the courthouse. So I don't worry about it at all."

Christie's administration has spent more than $1 million on out-of-state security costs since he took office in 2010.

Christie has been spending the majority of his time on the road in recent weeks as he campaigns in a crowded field of GOP candidates. He was in New Hampshire earlier this week.