AUGUSTA – Republican Sen. Susan Collins’ campaign on Friday proposed that supporters of Democratic Rep. Tom Allen enter into negotiations to develop ground rules for a me-and-my-shadow campaign trail practice known as tracking that is common elsewhere but unusual in Maine.

Several days of dispute between the rival camps have followed an incident last weekend in which a Democratic Party staffer closely trailed Collins with a video camera at a parade in Stockton Springs.

In an “open letter” to the Allen campaign, Collins’ chief of staff, Steve Abbott, complained about “this intrusive process” and said it had “no place in Maine politics.”

Collins subsequently suggested that one area of concern was the privacy of constituents who might want to talk to her in casual encounters.

Democrats shrugged off the Republican complaints, saying it was standard practice to monitor opponents and denying that the parade filming had been intrusive. Democratic Party spokeswoman Carol Andrews also said both sides do the same thing.

On Friday, Abbott pressed the Republican case, offering “a proposed memorandum of understanding on the issue of tracking.”

It listed “acceptable practices,” such as recording an opponent at a forum, and “unacceptable practices,” such as recording a candidate’s conversations.

“While tracking has become a popular tactic nationally, it has still not been extensively or systematically employed in Maine,” Abbott wrote. “We have the responsibility to attempt to conduct a campaign that will inform voters and make Mainers proud. An agreement to not engage in this practice could help start us down the right road.”

Allen said Friday he had been the subject of videotaping of unknown sponsorship and dismissed the practice as “a standard opposition research” tool aimed at learning what politically noteworthy things other candidates were saying.