WASHINGTON — A constitutional amendment to ban flag desecration died in a cliffhanger vote in the Senate this afternoon, a week before Independence Day, one vote short of the support needed to send it to the states for ratification.

The 66-34 vote in favor of the amendment was a single vote short of the two-thirds required. The House surpassed that threshold last year, 286-130.

The proposed amendment, sponsored by Sen. Orrin Hatch, R-Utah, read: "The Congress shall have power to prohibit the physical desecration of the flag of the United States."

It represented Congress' response to Supreme Court rulings in 1989 and 1990 that burning and other desecrations of the flag are protected as free speech by the First Amendment to the Constitution.

Senate supporters said the flag amounts to a national monument in cloth that represents freedom and the sacrifice of American troops.

"Countless men and women have died defending that flag," said Majority Leader Bill Frist, R-Tenn., closing two days of debate. "It is but a small humble act for us to defend it."

Opponents said the amendment would violate the First Amendment right to free speech. And some Democrats complained that majority Republicans were exploiting people's patriotism for political advantage in the midterm elections.

"Our country's unique because our dissidents have a voice," said Sen. Daniel Inouye, D-Hawaii, a World War II veteran who lost an arm in the war and was decorated with the Medal of Honor.

"While I take offense at disrespect to the flag," he said, "I nonetheless believe it is my continued duty as a veteran, as an American citizen, and as a United States senator to defend the constitutional right of protesters to use the flag in nonviolent speech."

The Senate also rejected an alternative put forward by assistant Democratic leader Dick Durbin of Illinois. It would have made it against the law to damage the flag on federal land or with the intent of breaching the peace or intimidation. It also would have prohibited unapproved demonstrations at military funerals.