As Montana same-sex couples have challenged a same-sex marriage ban there, only two states in the US now have same-sex marriage bans unchallenged in court.

Five gay and lesbian couples in the US state of Alaska filed a lawsuit last Monday challenging the state’s ban on same-sex marriage, leaving only three states with unchallenged bans.

Then yesterday, four couples in the state of Montana filed a lawsuit challenging the state’s ban on same-sex marriage.

The number will reportedly soon fall to one, as a lawsuit is set to be filed in South Dakota in the near future.

There are 29 US states with legal challenges against same-sex marriage bans. Another 19, and the District of Columbia allow same-sex couples to marry.

Nancy Robrahn, 68, and Jennie Rosenkranz, 72, have been together for 27 years. They plan to marry in the state of Minnesota, before coming back to South Dakota to challenge its ban on equal marriage, and recognising same-sex marriages.

South and North Dakota are now the only two states with same-sex marriage bans without lawsuits challenging them.

Arkansas couples have already begun to wed since a ruling two weeks ago striking down that state’s ban. Over 300 couples have received marriage licences despite the ban still being defended.

Dozens of gay and lesbian couples in the US state of Pennsylvania rushed this week to obtain marriage licences, as a judge struck down its same-sex marriage ban. There is a three-day waiting period for marriage there, so despite there being no defence of the ban, weddings won’t start there until the weekend.

A 1996 state law defined marriage as between one man and one woman, but in a Tuesday ruling, US District Judge John Jones ruled that the ban was unconstitutional.