Leaders of both parties in Congress yesterday supported the idea of creating a Department of Homeland Security by Sept. 11, even as they hinted they might seek substantial changes to President Bush's proposal for the biggest reorganization of the federal government in more than 50 years. 

House Minority Leader Richard A. Gephardt (D-Mo.) pressed for the target date during a White House meeting of congressional leaders and Bush. Sources said the president called the goal -- which would coincide with the first anniversary of the terrorist attacks on New York and the Pentagon -- "bold." 

"Bolder is better," Bush said, according to people familiar with the session. After the meeting, Bush and Homeland Security Director Tom Ridge traveled to Kansas City, Mo., where the president urged an audience to push Congress to approve the proposal, saying he needed the public's help to overcome legislative turf battles. 

Lawmakers could find it difficult to enact the complex legislation -- which House Speaker J. Dennis Hastert (R-Ill.) called "a heavy lift" at the White House meeting -- by Sept. 11. But presidential support for the target could ease potential tensions between congressional Democrats and Republicans. Some Democrats have privately worried that GOP leaders might delay passage of the bill until November in hopes of keeping voters' attention on anti-terrorism efforts -- a topic generally thought to favor the president's party. 

House Majority Leader Richard K. Armey (R-Tex.) said he and other lawmakers "understood the symbolism" of enacting the legislation by Sept. 11. 

"We will all have to work hard and somewhat double-time to get it done," Armey said. "But if we have the level of cooperation and commitment I perceived this morning, I think we can do that." 

House leaders say they are close to deciding how best to move the president's proposal through their chamber. According to several Republicans, Hastert leans toward creating a select committee to handle the bill. Eighty-eight congressional committees and subcommittees have some jurisdiction over homeland security. 

GOP Conference Committee Chairman J.C. Watts (R-Okla.) said it "makes sense" to create a "leadership-driven committee" to shepherd the measure through the House. Armey is likely to chair such a committee, GOP aides said, though leaders have yet to determine the panel's makeup. 

While lawmakers from both parties said they were eager to act on Bush's proposal, they also made it clear they might alter it. Armey, for example, said he might support moving the CIA and FBI into the proposed department. That would amount to a major departure from Bush's plan. 

White House officials said it will take two or three weeks for them to submit details of the legislation to create the department, which will affect all or parts of 22 federal agencies and nearly 170,000 employees. Ridge has said he will testify before Congress once the legislation is submitted. He plans to brief House members in a closed session today and hopes to have a similar session with senators later this week. 

In the first sign of the debate to come, several lawmakers questioned the proposed department's makeup at a congressional hearing yesterday. The session, convened by two panels from the House Government Reform Committee, was scheduled weeks ago to deal with homeland security. It turned into an early test of Bush's proposal, with most participants supporting the idea's basic framework. 

The hearing featured testimony from six legislators who introduced their own proposal for a homeland security agency this spring -- a model much like the one described by Bush last week -- as well as from senior officials from six agencies that would be relocated. 

Several legislators questioned the proposed department's ability to obtain and analyze information from the CIA, FBI and other intelligence-gathering agencies. The White House envisions the department as a clearinghouse for intelligence about terrorist threats, not as a manager or information-gatherer. But several lawmakers said the department's role must be strengthened to avoid the kind of lapses uncovered in a congressional investigation into what the FBI and CIA knew about potential terrorists before the Sept. 11 attacks. 

"I'm wondering if our first priority ought to be addressing those clear failures and then addressing what may be longer-term problems," said Rep. Janice D. Schakowsky (D-Ill.). 

Sen. Joseph I. Lieberman (D-Conn.), one of the hearing's witnesses, said Congress should consider putting parts of the FBI that handle domestic intelligence into the new department. But that decision could wait, he said, because "it may be more than we can bite off and absorb this year." 

Others questioned why some agencies, such as the Federal Emergency Management Agency, the Coast Guard and the Customs Service, would enter the department intact, even though they handle many non-terror functions. 

White House officials have said those agencies would be able to meet all responsibilities, and it would have been unwieldy to break them up. White House spokesman Ari Fleischer said the combination of agencies to form the Homeland Security Department will create "redundancies that would be eliminated."