DOVER — Delaware became the 11th state May 7 to legalize same-sex marriage.

DOVER — Delaware became the 11th state May 7 to legalize same-sex marriage after a lengthy debate in the state Senate that saw one lawmaker disclose her longtime same-sex relationship and the surprise support of two senators who could have tipped the outcome the other way.

A half-hour after the 12-9 Senate vote, Gov. Jack Markell signed the bill into law on the main stairs in the lobby of Legislative Hall.

“Delaware should be, is and will be, a welcoming place to live, love and raise a family for all who call our great state home,” Markell said.

Swing-vote senators Bethany Hall-Long, D-Middletown, and Catherine Cloutier, R-Brandywine Hundred, voted in favor of the legislation. Cloutier was the lone Republican “yes” vote in the Senate and one of two in the General Assembly. Two Senate Democrats, Robert Venables, of Laurel, and Bruce Ennis, of Smyrna, voted no.

Delawareans will be able to enter into same-sex marriages effective July 1. The law abolishes a prohibition against same-sex marriages established in 1996 and replaces a civil unions law passed in 2011.

The law provides a mechanism for converting existing same-sex civil unions established in Delaware to marriages. A year after the effective date, all civil unions will automatically be converted to marriages.

The law states that no church or clergy member will be compelled to solemnize a same-sex marriage. Delaware’s existing public accommodation law outlaws discrimination based on sexual orientation.

Proponents of the legislation and its sponsoring lawmakers cheered the victory, while those who opposed the measure reacted with shock and promises to unseat the lawmakers who voted for the bill.

Democratic Sen. Karen Peterson, one of the bill’s sponsors, said opponents’ arguments are rooted in the notion that being gay or lesbian is a choice but that she cannot remember when she chose to love another woman.

Peterson came out publicly for the first time on the Senate floor during debate, referencing her 24-year relationship with her partner.