A new survey by the Washington Post and ABC News has found that three-quarters of Americans think that openly gay, lesbian and bisexual people should be allowed to serve in the military.

64% of Republicans and nearly two thirds of self-described conservatives backed a change in the current law, as did 57% of white evangelical Protestants and 82% of white Catholics.

It was Republican opposition that forced then-President Bill Clinton to abandon his pledge to allow gay people to serve and signed into law the compromise known as “Don’t Ask, Don’t Tell.”

Since 1993 gay people who do not reveal their sexuality can serve, and commanding officers are not meant to ask service personnel about their sexual orientation.

More than 12,000 gay men and women have been discharged under the current law, at an estimated cost of more than $363 million (£182.6m).

The new poll of 1,119 Americans, taken earlier this month, shows how support for gays in the military has steadily increased, from 44% in 1993 to 62% in 2001 to 75% today.

The current policy prohibits anyone who “demonstrates a propensity or intent to engage in homosexual acts” to serve in the US Armed Forces.

“A lot of service members are getting ‘wink-wink’ treatment from their commanders,” said Aaron Belkin, director of the Palm Centre at the University of California, which studies the policy.

In May the Chairman of the US Joint Chiefs of Staff said that Congress, and not the military, is responsible for the ban on openly lesbian, gay and bisexual Americans from military service.

Speaking to graduating cadets at West Point military academy, Admiral Mike Mullen said that “Don’t Ask, Don’t Tell” is a law that the Armed Forces follow.

“Should the law change, the military will carry that out too,” he said.

An estimated 65,000 lesbian and gay service members serve on active duty and in the reserves of the United States military, according to gay advocacy group the Servicemembers Legal Defence Network.

It said it knows of about 500 gay army members who are serving openly without any consequences.

During his Senate confirmation hearing last year, Admiral Mullen told lawmakers:

“I really think it is for the American people to come forward, really through this body, to both debate that policy and make changes, if that’s appropriate.

“I’d love to have Congress make its own decisions with respect to considering repeal.”

The most senior US military veteran in the House of Representatives has called for an end to the ban.

Democrat Congressman Joe Sestak, who served 31 years in the Navy, retiring with the rank of three-star Admiral, is one of seventeen veterans in Congress who want to repeal “Don’t Ask, Don’t Tell.”

150 of his Congressional colleagues have lent their support to the Military Readiness Enhancement Act, which would repeal the law.

In March US Democratic Presidential candidate Barack Obama told leading gay publication The Advocate he supports a repeal of the gay ban and is hopeful it can be achieved.

His Republican opponent John McCain does not favour gays serving openly.