RICHMOND, VA. ? Virginia lawmakers gave final legislative approval Wednesday to a proposed constitutional amendment to ban gay marriage, despite warnings the measure is so broadly worded it could have dire unintended consequences for all unmarried couples.

The 28-11 Senate vote, combined with the House’s earlier passage, clears the way for the proposed amendment to be placed on the November ballot.

If voters approve it, Virginia will join 18 other states with constitutional amendments against gay marriage. Most of those amendments were adopted after Massachusetts’ highest court legalized gay marriage in 2003.

Gay marriage is already against the law in Virginia, but lawmakers said an amendment was needed as extra insurance to stave off a court ruling like the one in Massachusetts.