Two senior House Democrats called on President Bush yesterday to declare whether he supports a bill that would repeal virtually all of the District's gun laws, as GOP House leaders scheduled a vote on the measure tomorrow.

Backers of the legislation -- which more than half of the 435-member House is sponsoring, including about 50 Democrats -- expect it to pass by a lopsided vote. But its prospects are uncertain in the Senate, which has turned back two other efforts this year to repeal D.C. gun limits.

The bill, sponsored by Rep. Mark Edward Souder (R-Ind.), would end the city's stringent bans on handguns and semiautomatic weapons, lift registration requirements for ammunition and other weapons, and decriminalize possession of unregistered firearms and carrying a handgun in one's home or office.

In their letter to Bush, Reps. Henry A. Waxman (D-Calif.) and John Conyers Jr. (D-Mich.) said the bill would "undo many of the security measures that have been put into place" in the nation's capital since the 2001 terrorist attacks.

They wrote that if the bill became law, "someone could legally possess a semiautomatic [.50-caliber] sniper rifle and armor piercing ammunition in an apartment overlooking . . . Connecticut Avenue, a common route for motorcades.

"Ice cream and hot dog vendors [on the Mall] could be armed with assault weapons. . . . A Capitol Hill resident who lived across the street from the U.S. Supreme Court could sit on his porch with a fully-loaded semiautomatic Uzi Carbine."

The lawmakers added, "We want to know where you and your Administration stand on this bill," and they accused the president of failing to lobby for an extension of the federal assault weapons ban this year.

White House spokeswoman Clare Buchan declined to comment yesterday on the specifics of Souder's bill. "The president believes that law-abiding citizens have an individual right to own firearms, and the president looks forward to working with Congress to achieve this goal while we continue to vigorously prosecute the criminal misuse of guns," Buchan said.

Supporters of the gun-ban repeal have said the city's laws violate the Constitution's Second Amendment.

"We are committed to restoring the right to self-defense of one's home and family from criminal attack," said Chris Cox, the National Rifle Association's chief lobbyist. "We don't feel like lawful D.C. residents should be treated as second-class citizens."

The 13-member D.C. Council reiterated its unified opposition to the bill at a news conference yesterday.

Opponents of Souder's bill say House GOP leaders are pushing it in order to rally the party's gun rights base before the Nov. 2 election.

"It is shocking that the House of Representatives would put the safety of the citizens of the District of Columbia, the workers, including the members of Congress, and the many visitors to the city in jeopardy for political purposes," said council Chairman Linda W. Cropp (D-At Large).

Northern Virginia Rep. Thomas M. Davis III, Republican chairman of the House Government Reform Committee, joined Waxman in urging the House to vote no and noting that House GOP leaders bypassed the panel to get Souder's bill to the floor.

"Although one can debate the merits of some of D.C.'s gun laws, no one should question the importance of keeping fully loaded assault weapons off the streets of the nation's capital city," Davis and Waxman wrote in a letter to House colleagues.

Supporters of the repeal say the city's 28-year-old gun bans have been ineffective, pointing to the increase in the District's homicide rate. Federal data show that the District's rate rose 72 percent from 1976 to 2001, when the national rate fell 36 percent.

Repeal opponents note that D.C. homicides have fallen 24 percent this year. They also cite statistics showing that D.C. police recovered 1,385 guns from Jan. 1 to Sept. 8 and that 97 percent of the guns used in D.C. crimes come from elsewhere.