Calling it the Allard Amendment, the proposed amendment states that marriage in the U.S. will only be recognized as involving a man and a woman.
"Neither this Constitution, nor the constitution of any state, shall be construed to require that marriage or the legal incidents thereof be conferred upon any union other than the union of a man and a woman," the amendment states.
Strongly backed by The Christian Coalition of America and many other arch-conservative groups, a ban on gay marriage was endorsed by President George Bush in February of this year after several states, including San Francisco, let loose with a flurry of marriages seen by many as unlawful.
The Senate's decision on the ban overshadows the start of the Democratic presidential convention in Massachusetts and is expected to be an untimely political decision for many democratic senators, particularly since Massachusetts was the first state to recognize lesbian and gay marriages.
The amendment is scheduled to appear on the Senate floor by July 12, although there is some speculation that getting a two-thirds majority vote could be difficult at a time when both political parties are wrapped up in a popularity contest with the American public, particularly the Democrats who are counting on gaining speed toward the November election at a time when President George Bush's approval rating is at an all-time low.
While presidential contender Sen. John Kerry has taken a more mainstream, liberal stance on the issue of gay marriage, suggesting that the issue be left up to individual states to decide, Bush has held fast and strong to his conservative Republican roots.
Some critics of the amendment assert that introducing the controversial amendment in the Senate five months before the presidential election is a deliberate effort to fragment the democratic vote.
But Sen. John Cornyn, R-Texas, a main backer of the amendment and a staunch supporter of maintaining the "integrity" of the "most venerable social institution," denied that there is any political agenda behind getting the amendment passed at such a volatile time for lawmakers.
"This was an issue that was thrust upon us by the Massachusetts Supreme Court," said Cornyn. "We didn't pick the battle, we didn't pick the timing."
Some Bush advisors are pushing Bush to throw his weight behind the ban, which is expected to win favor with a huge number of conservative voters. In particular, Bush is being advised by Coalitions for America to shift his political focus from the war in Iraq to banning gay marriage.
According to the Associated Press, amendments to the Constitution require approval by two-thirds majorities in the House and Senate and ratification by three-fourths of state legislatures.