Democrat Jennifer Granholm vetoed repeal attempts in 2006 and 2008 when she was governor.
"The fact this could make it through both chambers and make its way to the governor's desk is fine by me, irrespective of whose name is on it," Rep. Richard LeBlanc, a Democrat and biker who has introduced a partial repeal bill, told The Detroit News. "It's a personal liberty thing."
His bill would let riders 21 or older go without helmets if they carry at least $20,000 in insurance to cover medical expenses in case of an accident.
A bipartisan Senate bill would lift the requirement for all adult riders who pass a safety course.
"What I've been told is they can see and hear better" without a helmet, Sen. John Gleason, a Democrat, said in explaining his support for the measure.
But opponents such as emergency room doctors and insurance companies warn of more deaths and serious injuries.
They point to National Highway Traffic Safety Administration studies predicting hundreds of lives would be saved annually nationwide if all motorcyclists wore helmets.