Republican Senate hopeful Jack E. Robinson's campaign manager announced last night he is quitting after two months on the job.

Tom McCuin, Robinson's only paid staff member, said he was leaving the campaign because of strategy disagreements in Robinson's challenge to US Senator Edward M. Kennedy. "Over the past few weeks, we've had increasing disagreements over strategy and tactics," McCuin said. "I felt that at this point in the election, I could be more effective helping some other candidates around the state."

Robinson, reached last night, said that he bore no ill feelings about McCuin's departure.

"I accept Tom's resignation with regret but the campaign goes on," he said. "This is an unconventional campaign and it requires unconventional people."

McCuin, 33, of Groton, cut his political teeth working for Augusta Hornblower, a Republican state representative, from 1985 until her death in 1994. This winter, he was a paid worker in US Senator John McCain's New Hampshire Republican presidential primary effort.

McCuin was a McCain delegate to the Republican National Convention. While there, he helped Robinson gain admission to delegation events and get interviews with radio talk-show hosts.

He also accompanied Robinson on a series of road trips across the state, as the candidate fulfilled his pledge to visit every Massachusetts city and town - even if only for a few seconds at a time.

Early in the campaign, Robinson vowed to raise $7 million. As the campaign wore on and his fund-raising goals fell short - as of last week, he had only raised between $20,000 and $25,000 since July 1 - Robinson announced a more radical campaign concept.

"Our campaign headquarters is in cyberspace," Robinson told the Globe last week. "We will not have a brick-and-mortar headquarters. We are going to rewrite the rules for campaigning in the new-age economy."

McCuin declined to comment on his specific differences with Robinson's tactics, but said he wished his former boss well.

Also on the ballot are Libertarian Carla Howell, Natural Law candidate Dale E. Friedgen, and Constitution Party candidate Philip Lawler and Timesizing.com Party candidate Philip Hyde.