Conservation groups want to use oil taxes to protect the state's environment, but schools, businesses and the oil industry have different priorities. Voters will decide in November.
The state's economy is attracting 1,500 new residents a day, but growth is costing billions of extra dollars in road and traffic maintenance every year.
While more than a dozen states are fighting the new federal rules to reduce carbon emissions, many officials fear that ignoring them would be far worse.
After two decades of leaving its gas tax untouched, Massachusetts tied the rate to inflation. In November, voters could join the list of states that repealed the automatic increase.