OLYMPIA, Wash. --- A new Washington state Senate bill (SB 6923) seeks to impose a vehicle excise tax on passenger vehicles based on EPA fuel-efficiency ratings, but commercial drivers would be exempt, the Seattle Post-Intelligencer reported.

Under the bill, the owner of a Toyota Prius, for example, would pay $60 in annual taxes, while a Hummer H3 owner would pay $180.

Introduced by State Senator Ed Murray (D-Seattle), the bill stipulates that the money raised would be split between the state Department of Transportation and local governments. Seventy-five percent would go to cities and counties, while 25 percent would go to Department of Transportation projects, including "green" alternatives.

Seattle Mayor Greg Nickels supports the bill. But critics argue the bill's tax would hit lower-income drivers hardest.

Because the legislation was introduced so late in the session, it's not clear whether the bill will move forward.