By CHRISTOPHER MARQUIS
 
WASHINGTON, July 28 - The Bush administration, which has undertaken a number of tough measures against Cuba in this pre-election season, is finding opposition to some of them from large numbers of Cuban-Americans, a group whose electoral support the White House hoped to solidify.

Administration officials say their strategy is intended to hasten the end of Fidel Castro's government, provide aid to a transition government and help establish a democratic free-market state.

"Our goal is to liberate the Cuban people from the tyranny and from dependency on international charity," Roger F. Noriega, assistant secretary of state, told reporters in May, when the new restrictions were announced. "We want them to control their own destinies, to be free to make choices on how they want to live their lives."

But critics say the measures, which were laid out in a policy report from a presidential commission led by Secretary of State Colin L. Powell, are chiefly intended to add to backing for President Bush among Cuban-Americans, a group White House advisers have acknowledged is central to his re-election strategy.

Paradoxically, some of the critics say, several provisions - like a tightening of travel restrictions and a curb on relief packages - may backfire, harming Mr. Bush's chances in Florida, a crucial swing state.

The strategy was drafted largely by administration officials who were once aides to Senator Jesse Helms of North Carolina, now retired, the author of hotly contested anti-Castro legislation enacted a decade ago. It was thought that the policy would appeal to longtime exiles with few family ties to Cuba and a deep-seated desire to eliminate the Castro government. Such people voted for Mr. Bush by more than four to one in 2000, pollsters say.

But the strategy has pumped life into a voter registration drive among newer Cuban immigrants, who generally favor greater contact with the island and their relatives there.

Sergio Bendixen, a longtime pollster based in Miami, said the new measures were drawing supporters and opponents in equal numbers among Cuban-Americans. For a bloc that has been characterized by remarkable electoral cohesion for decades, the split is telling, Mr. Bendixen said.

"They've been very controversial," he said of the new restrictions. "The Bush side feels it's going to energize their base. The Democrats feel it has created a very important opening to gain significant support."

Jorge Mursuli of Mi Familia Vota, a voter registration drive among Hispanics in Florida, said his nonpartisan operation was signing up as many Democrats as Republicans.

"It shows you the potential this issue has to blow up in their faces," Mr. Mursuli said of the president and his advisers on Cuba.

The document prepared by the presidential commission listed about 675 specific policy recommendations, many of them steps the administration would favor after Mr. Castro was gone. American involvement, if the successor government requests it, is offered in areas as diverse as tax collection, environmental protection, cultural preservation, mortgage financing and labor relations. Involvement so detailed, critics say, would amount to dictates from the United States, which is likely to control the economic levers of a Cuban recovery.

But the travel provisions are the most controversial of the new measures. Already adopted by the administration, they limit Cuban-Americans to one family visit to the island every three years - down from one a year - with no exceptions, as in a death in the family. Administration officials say they are trying to deprive the Castro government of much-needed cash that visiting exiles bring.

As for people other than Cuban-Americans, tourism per se to the island has long been barred - some limited educational and cultural travel is allowed - and the administration plans to tighten enforcement of the ban.

In addition to the new travel restrictions on Cuban-Americans, the administration also initially prohibited sending clothes, personal hygiene items, seeds and other basics to family members in Cuba, saying the government there benefited by charging exorbitant commissions to deliver them. (The shipment of medicine and some other provisions was permitted.) It also ruled out packages of any kind for extended-family members.

Then, earlier this month, a heated debate ensued in the House, where Representative Jeff Flake, Republican of Arizona, proposed easing the parcel rules, portraying them as anti-family. "Withholding of such basic items will have little effect on Castro,'' Mr. Flake said, "and a significant effect on individuals who already struggle for the basics.''

Representative Lincoln Diaz-Balart, a Florida Republican who is a leading advocate of the tougher measures, said Mr. Flake's proposal would "serve the interest of a brutal dictatorship."

"We recognize that many common Cubans will be severely affected, and especially the children, the elderly and the ill,'' Mr. Diaz-Balart said. "But we, as members of the Cuban opposition, will try to care for those families as best we can.''

After the House voted 221 to 194 to soften the rules on parcels, the administration eased its regulations, placing personal hygiene products on the list of allowed items.

Joe Garcia, executive director of the Cuban American National Foundation, based in Miami, said the restrictions adopted by the administration amounted to "bad policy and bad politics." Although his longtime anti-Castro organization, the largest exile lobby, supports most provisions in the new strategy, the restrictions on travel and relief packages have changed the focus of debate, he said, away from Mr. Castro's human rights record and the persecution of dissidents.

"We succeeded in turning Castro versus the U.S. government into David versus Goliath,'' Mr. Garcia said. "The giant is perceived as being abusive."