HELENA, Mont. (AP) — Gov. Steve Bullock's former campaign is rebutting allegations from a Billings businessman that the campaign illegally coordinated activities with third-party groups.

James Pennington filed the complaint in mid-March saying the campaign and several groups wrongly coordinated activities through political vendor Hilltop Public Solutions.

The complaint relies on financial disclosure filings with the Commissioner of Political Practice showing campaign staffers spoke with Hilltop agents that were "supposedly involved in otherwise independent campaigning."

It is illegal for candidates to coordinate spending with third-party groups. It is seen as a potential way to circumvent campaign contribution limits.

Lee Newspapers of Montana reports that attorneys for Hilltop and the Bullock campaign deny Pennington's charges.

They say the campaign simply was using the same vendor that was providing services to many Democratic-aligned third-party groups.