The pro-medical marijuana effort was bankrolled almost entirely by Ohio billionaire Peter Lewis, chairman of the board of the auto insurer Progressive Corp., who has helped fund similar efforts in other states.
In contrast, the Massachusetts Prevention Alliance, which was opposed, raised just $3,300.
"We just didn't have enough time and we certainly didn't have enough money. We got outspent 1 million to 1 by a guy from Ohio," said John Sofis Scheft, a spokesman for the opposition group.
If the suicide ballot question passes, Massachusetts would become the third state, after Oregon and Washington, to legalize physician-assisted suicide for people with terminal illnesses.
The auto repair law was the source of some confusion. Supporters first joined with auto manufacturers in urging voters to skip it but then changed course and encouraged voters to say yes.
The confusion came because both sides reached a compromise that was later approved by lawmakers and signed by Democratic Gov. Deval Patrick, but not in time to remove the question from the ballot.
The compromise bill approved by lawmakers on the final day of the legislative session in July included some concessions to automakers. The industry has until 2018 to satisfy a mandate that all new cars sold in the state include onboard diagnostic and repair information systems that can easily be accessed with any typical laptop computer.
Passage of the ballot question supersedes the new law, but that would not preclude the Legislature from making further changes, or even reinstating the compromise, when it returns to Beacon Hill in January.