Secretary of State Colin L. Powell gave Mexican officials a sober report Tuesday on the prospects of winning congressional approval to grant legal status to millions of undocumented aliens in the United States. He said President Bush would place a "high priority" on pushing his stalled plan through Congress, but he said he did not want to "overpromise" success.

Bush unveiled the plan 10 months ago, but it received a lukewarm reception on Capitol Hill and the administration made little effort to promote it during the election year. In last week's election, Bush received about 44 percent of the Hispanic vote, up from 35 percent in 2000, exit polls indicated. Mexican President Vincente Fox has made it clear that he hopes to seize the moment to achieve an agreement on migration.

In 2001, Fox said he was looking for the "whole enchilada" on immigration. But Powell told the Televisa television network Tuesday that that phrase created impossible expectations. "We are taking little bites of the enchilada, and not the whole enchilada at once," he said.

Bush's plan would make the 8 million undocumented immigrants in the United States eligible for temporary legal status for at least six years, as long as they are employed. But it would not automatically put them on a path to obtaining citizenship or even permanent resident status. Bush has said most "temporary workers" would eventually have to leave the United States.

Since Bush's reelection, Fox has repeatedly said he believes the climate favors progress on immigration reform in the United States, which is Mexico's top foreign policy priority. The terror attacks of Sept. 11, 2001, derailed Fox's earlier hopes of reaching a broad agreement.

Powell and Homeland Security Secretary Tom Ridge met with Fox for 30 minutes. A spokesman for Fox, Agustin Gutierrez Canet, said later that Fox "expressed satisfaction with the announcement that the U.S. government is going to give a high priority to migration reform during the second Bush term."

Many Mexicans remain skeptical that the United States is serious about immigration reform, particularly after strong Republican gains in Congress in last week's elections. Republican lawmakers have been among the biggest skeptics of Bush's plan. In another sign of American sentiments, Arizona voters approved a referendum cracking down on illegal aliens receiving public benefits.

"Fox is absolutely crazy to think anything will happen on migration," said Jorge Montano, a former Mexican ambassador to the United States. "I thought we had learned that lesson, but I guess we did not. He's trying to sell the same thing he was trying to sell four years ago, and I don't think it's something that people will swallow in the United States."

Powell, who was joined by five fellow members of Bush's Cabinet for the annual U.S.-Mexico Binational Commission meeting, opened the session by declaring that "the president is committed to comprehensive immigration reform as a high priority in his second term, and he will work closely with our Congress to achieve this goal."

Later, at a news conference, Powell said that migration had been a difficult issue to tackle in an election year but that he sensed the ground had shifted.

"Now that our election is over and we also are coming out of the 9/11 period and doing a better job of securing our borders, and as we have the president reelected for a second term and a new Congress coming in as well, we think that the environment has improved significantly for this kind of reform," he said.

Powell added, "At the same time, we don't want to overpromise." He said the administration "will make an assessment with the new Congress of the pace at which we can proceed with the temporary work programs, and how fast and how far we can move and over what period of time." But Denise Dresser, a political scientist here, said Mexico "is just dreaming" to believe it will win significant immigration reforms in the United States. She said no amount of pressure exerted by Mexico would affect the immigration debate, which she said was strictly a U.S. domestic political issue.

"Bush will pursue it if he thinks it will help the Republican Party," she said. "Fox keeps stumbling over the same stone over and over again. He sees this visit as the possibility of what was put in a drawer being taken out again. I think he's deluded to believe that."

Geronimo Gutierrez, head of North American affairs in the Mexican Foreign Ministry, said Mexico understands that the debate over immigration has changed in the United States since 2001. Immigration is now viewed mainly as a homeland security issue, he said, and Mexico has argued that creating a "safe, legal and orderly" flow of workers into the United States improves security.

"We have had unprecedented levels of cooperation on border security issues," Gutierrez said. "The United States is appreciative of what we have been able to accomplish on border security, which is linked to the broader immigration issue."

President Vicente Fox of Mexico, right, talks with Secretary of State Colin L. Powell at Fox's official residence in Mexico City. Powell said he did not want to "overpromise" success in Congress for a proposal to grant legal status to undocumented aliens.