Washington (CNN) Virginia on Monday finalized its ratification of the Equal Rights Amendment, a potential milestone in the century-long effort but one that faces significant legal obstacles.

The commonwealth could be the 38th state to ratify the ERA, which would ban discrimination on the basis of sex and guarantee equality for women under the Constitution, but there are big legal questions as to whether that ratification stands. The approval of three-fourths of state legislatures are required to ratify an amendment, though several states that formerly passed the ERA decades ago have since rescinded their support, and opponents point to a since-expired congressional deadline in arguing that the window for ratifying the amendment has closed.

The US House will vote on February 10 on whether to rescind that deadline, according to Majority Leader Steny Hoyer's office.

Progressives, however, reject those arguments, and passing the ERA has been an urgent priority for Virginia Democrats, who control both houses of the state legislature and passed the ERA in both chambers earlier this month

Cheers broke out in the chamber after the state Senate voted 27-12 on Monday to pass the state House of Delegates resolution to ratify the ERA. The House had passed the resolution on January 15. Later Monday, the State House of Delegates adopted the state Senate's resolution by a vote of 58-40.

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