More than 500 people flocked to the house chamber in Montpelier, Vermont, last night to testify on same-sex marriage in the state.

Amidst a week of hearings, the public debate last three hours and saw 115 people testify in favour of gay marriage and 85 against it.

Vermont residents spoke before the house and senate judiciary committees.

The senate judiciary committee is expected to vote on the legislation by Friday, after which it will move to the house. If the legislation succeeds, gay marriages would begin in September.

If the bill is approved, the state will join Massachusetts and Connecticut as the only US states that allow gay marriage.

Civil unions in Vermont were legalised in 2000 but offered only some of the benefits available to straight married couples.

The new bill will grant gay and lesbian couples access to Social Security benefits available to straight married couples. They would also be able to claim joint health insurance and make emergency medical decisions.