Primarily Republican, US senators have voted to block a debate this evening into gay and lesbian people being able to serve openly in the military.

A minimum of 60 senators were required to be in favour of overturning a filibuster of the ‘defense authorisation bill’ which includes the repeal of the US military ‘Don’t ask, Don’t tell’ policy by senator John McCain but only 56 senators voted in favour. Although some of the senators who voted against did so because of an immigration amendment ‘tacked’ onto the bill.

The vote comes after a high-profile campaign by the singer Lady Gaga which has included her wearing a dress made from meat at the MTV Video Music Awards and posting a video message to YouTube where she appealed directly to a number of Republican senators to support the vote for a debate and ultimately to repeal the ‘Don’t Ask, Don’t Tell’ policy.

It is feared that tonight’s vote will mean that it will not be possible for ‘Don’t Ask, Don’t Tell’ to be debated again before the United States goes to the polls for the mid term elections. Although it is still possible for the Senate to vote again during the so called ‘lame-duck’ session that takes place between the election and the swearing in of new members.

Several moderate Republican senators have actually said they would support the lifting of the ban, but only after a Pentagon review into the impact of repealing the ban on troop readiness and morale reports to President Obama on December 1st.

Former Republican presidential nominee senator John McCain spoke against holding the debate prior to the Pentagon review being published: “The most fundamental thing we could do to honour the sacrifice of our troops is to take the time to hear their views.”

“This ain’t over,” Senator Joseph Lieberman, the Independent senator for Connecticut, who authored the repeal Don’t Ask, Don’t Tell. “It’s long past time to repeal this policy.”

“The Democrats have been against ‘Don’t Ask, Don’t Tell’ for more than a decade and why we allowed this law to remain in effect for another two years is beyond me,” Richard Soccarides, a former gay rights adviser to┬áPresident Bill Clinton told the Los Angeles Times. “I think we as a gay community all bear a significant share of responsibility for not insisting that the unconstitutional and discriminatory policy not be ended right away.”

The failure to secure the debate will embarrass US president Barack Obama, who has on a number of occasions called for the law to be repealed. Tonight his spokesman Robert Gibbs said the White House was “disappointed” at the Senate vote, “but we’ll keep trying.”

“The president obviously continues to urge Congress to act, and is working as well with the Pentagon to see this come to fruition,” he added.

An estimated 14,000 members of the US military have been discharged for revealing their sexuality since the law was introduced in 1993.

The majority of military leaders who have spoken publicly about the law support its repeal. However, some oppose lifting the ban and say it will harm morale and recruitment, especially in the middle of two wars.

The law allows gay soldiers to serve in the military but they must not reveal their sexual orientation.