Senate bill 2819 would authorize utility Narragansett Electric - a subsidiary of National Grid - to enter into a power purchase agreement (PPA) with developer Deepwater Wind for the eight-turbine installation.
The two parties had agreed a PPA but it was rejected in March by the state Public Utilities Commission (PUC), which said the agreed price was too high.
The senate environment committee voted in favour of the bill on Tuesday, and the full senate passed the bill the same day.
It must also be passed by the state house of representatives and signed by governor Donald Carcieri, who has publicly supported the project, before it can be passed into law.
Deepwater Wind plans to build the 20MW wind farm to prove the viability of a larger project off the Rhode Island shore, with a capacity of at least 350MW.
Deepwater Wind and Rhode Island signed a legally binding joint development agreement for the larger wind project in 2009.
Rhode Island is one of 10 East Coast states have created the Atlantic Offshore Wind Energy Consortium, a group dedicated to promoting the development of wind energy on the US Outer Continental Shelf (OCS).