WASHINGTON – Worried that the tone of the immigration debate is pushing Hispanics away from the Republican Party, the White House is working with political strategists to create a broad new coalition of business groups and immigrant advocates to back a reform plan President Bush could promote in Congress and to minority voters in the 2006 elections.

The strategists say Mr. Bush is planning to make immigration a top-tier priority as early as this fall, once the current focus on a Supreme Court vacancy has passed. The push is being planned to coincide with next year’s campaigns for the House and Senate, in which Hispanic voters could be critical in several states, and it is part of a broader White House strategy to forge a long-lasting majority by drawing more minority voters.

Aiming for an air of bipartisanship, the White House-backed coalition, to be called Americans for Border and Economic Security, will be led by two former congressmen, Cal Dooley, a Democrat of California, and Dick Armey, a Republican of Texas. The chief organizer is one of the capital’s most important White House allies: a former Republican National Committee chairman, Ed Gillespie, who has hosted preliminary meetings in his Washington lobbying firm just blocks from the White House and has been advising the RNC on minority outreach.

The effort is designed to help Mr. Bush take control of an increasingly contentious debate that has threatened to split the Republican Party and undermine its outreach to Hispanic voters. While the White House has not laid out details for a plan, in January 2004 Bush proposed a guest-worker program that would be open to many illegal immigrants already in America and to prospective workers abroad.

A guest-worker program is favored by many Hispanics and by businesses, many of them major GOP donors who depend on a steady flow of workers from Mexico and other countries. The White House effort is aimed at satisfying these groups while also promoting tougher “border security” enforcement, an attempt to mollify a vocal bloc of cultural conservatives in the GOP – many of them in the House leadership – that argues undocumented workers present a security threat to the country and take some jobs that could be filled by Americans.

Some Republican strategists worry that the more extreme voices in this camp are alienating Hispanic voters with anti-immigrant language, and one goal of the new coalition is to marginalize those voices. Organizers said the coalition could help the GOP avoid the kind of political damage caused in the early 1990s by the anti-immigration campaign in California backed by then-governor Pete Wilson.

The issue has presented a quandary for Mr. Bush, who backed off his earlier calls for immigration reform after conservatives rebelled. Now, the White House hopes to reinvigorate the drive for new immigration laws – but this time, it wants to work in advance to ensure that the president is backed by a broad alliance of business and advocacy groups.

There are signs, however, that the administration effort is running into problems even as it begins: Several key business groups are hesitant to join the new coalition, questioning whether the administration can separate itself from the anti-immigration wing of the GOP that is promoting restrictive policies. And the party’s leading voices favoring stricter limits on immigration, such as Rep. Tom Tancredo, a Republican of Colorado, remain undaunted – pledging to intensify their own efforts.

Coalition organizers say that makes their work all the more timely.

“The politics of the Republican Party isn’t going to change by itself. It needs help,” said Terry Holt, a former spokesman for Bush’s 2004 re-election campaign, who works with Mr. Gillespie and is recruiting members for the new coalition. “Immigration needs advocates. And if those advocates engage, they can have a profound impact on the issue.”

Referring to the Hispanic vote, which turned out in larger numbers last year for Bush than in his 2000 campaign, Mr. Holt added: “There are great opportunities for Republicans, and also dangers if we don’t handle this properly.”

Organizers say the new coalition is patterned after similar groups formed to press for Bush’s overhaul of Social Security and his successful 2003 push for a Medicare prescription drug program – a new aspect of Republican strategy in which corporations and other interest groups are tapped to help move public opinion in favor of a Bush-backed policy initiative.

Corporations and advocacy groups with a direct interest in immigration – including those who need skilled high-tech workers, farm laborers, and university teaching assistants – are being aggressively targeted for membership. Those being courted include Microsoft Corporation, Wal-Mart Stores Incorporated. and groups representing academic institutions, restaurants, hotels, landscaping firms, hospitals, and nurses.

Organizers say this is the first time an effort has been made to bring these disparate groups together to focus on immigration issues.

Admission into the new coalition costs between $50,000 and $250,000. The proceeds are expected to pay for a political-style campaign for an approach to immigration combining heightened border security with a guest-worker program of some sort, creating an environment that the White House believes will be more favorable for Mr. Bush to step back into the fray.

However, complicating matters for the White House is a business community that, so far, has shown some resistance to entreaties from Messrs. Holt and Gillespie, wary both of the price tag for joining the coalition and of aligning itself with a White House that tends to accede to the demands of its base.