As he weathers dismal approval ratings and defections within his own party, President Bush is enlisting his closest compatriot — and one untouched by his administration’s political troubles — to lobby for his core education objective on Capitol Hill.

First lady Laura Bush has held a handful of small-group meetings at the White House in recent weeks, hoping to shore up support among GOP members for the reauthorization of the 2002 elementary and secondary education law (PL 107-110).

It’s a rare step into the public policy realm for Mrs. Bush, who for the most part has shied away from politics and legislative haggling during her husband’s first six years in office.

The foray comes at a time when Bush’s own popularity inside and outside Washington is near an all-time low — and is in particular need of a boost with those Republicans who believe the law Bush dubbed “No Child Left Behind” went overboard on federal mandates.

Laura Bush’s approval ratings are among the highest of anyone currently in the administration — a CNN poll in late 2006 had her at 76 percent.

“You use everything you can,” said Howard P. “Buck” McKeon of California, the ranking Republican on the House Education and Labor Committee, who has attended two meetings with Mrs. Bush and about a half-dozen House Republicans.

By all accounts, Mrs. Bush has been an effective advocate. She’s an experienced librarian who has devoted time to children’s literacy programs the law created. But whether she can make a difference in what is shaping up to be a highly contentious debate over the future of the law is unclear.

“She’s not someone you see as a policy heavyweight,” said Mary Kusler, Washington lobbyist for the American Association of School Administrators, which represents 13,000 superintendents.

“I think at this point the Bush administration is very concerned about their legacy,” Kusler said. “If that means having Laura Bush go out and meet with members of Congress on the reauthorization, then that’s what they are going to do.”

The first lady’s spokeswoman would not say who has attended the meetings or offer any details about the substance of the discussions.

“She was just talking about the successes of No Child Left Behind and the need for it to continue,” said Sally McDonough, Mrs. Bush’s communications director.

The idea to get Mrs. Bush involved came up during a meeting between McKeon and Education Secretary Margaret Spellings. The two sensed a number of Republicans potentially walking away from the administration on the education renewal, and Spellings had an idea.

“She said maybe it would help if we had Laura Bush working on it,” McKeon remembered. “I said, ‘Yeah, that would be good.’ ”

Working with Spellings, the first lady has invited at least two groups of House Republicans, as well as at least one group of senators, to the White House to discuss over coffee the importance of the reauthorization. Mrs. Bush has expressed her support for the law, discussed where the renewal stands and what those in attendance can do to help move the process along, according to a Republican aide.

“She’s viewed as good a lobbyist as you can get,” said Republican Rep. Michael N. Castle of Delaware, who has attended two meetings with Mrs. Bush.

“She’s very effective,” said Republican Sen. Orrin G. Hatch of Utah, who attended a meeting with senators.

Independent Sen. Joseph I. Lieberman of Connecticut also attended a meeting, and Mrs. Bush spoke with Democrat Edward M. Kennedy of Massachusetts, chairman of the Senate Health, Education, Labor and Pensions Committee, at a White House social function July 12.

“She comes with a professional background, not only as a librarian but also as someone who continues to do a good deal of reading with children,” Kennedy said. “So I think she’s respected and I would imagine people listen to her.”

How much of a role Mrs. Bush intends to play going forward is uncertain. But the president can use all the help he can get.

Earlier this month, McKeon indicated that he could not support any legislation that would not have a majority of GOP members behind it.

That could be an extremely difficult goal to reach, considering a competing measure (HR 1539), sponsored by Republican Peter Hoekstra of Michigan, already has 60 GOP cosponsors. That bill would, in Hoekstra’s words, make the law “voluntary” by letting states come up with their own ways to measure school performance.

Two weeks are left before lawmakers leave for the four-week August recess, and neither chamber has begun moving a measure. The law is set to expire at the end of September. A one-year extension kicks in if no action is taken; and even if that year passes, Congress can continue core elements of the law by appropriating money for its programs.

Complicating the lack of movement are significant policy debates that have emerged between Republicans and Democrats, particularly over the weight standardized testing should be given in determining adequate yearly progress — the centerpiece of the law once expected to be President Bush’s domestic legacy.

“I think it is getting pretty late,” said Sandy Kress, who served as a special adviser to Bush in 2001 and is largely credited with bringing various parties together to pass the original law.

Now lobbying for a coalition of business interests, Kress said the shortened time frame, the complexity of the issues, disagreements over key aspects of the law and a more partisan mood on Capitol Hill have dimmed the prospects for renewal.

“I think these are the more serious issues, rather than the president’s effectiveness,” Kress said.

Having Laura Bush out front on the issue might not be a silver bullet to win over the law’s critics, but she could salvage support among those who have yet to decide.

“I think the president recognizes there are some real problems with the reauthorization, especially in light of what Mr. McKeon said,” about needing a majority of Republicans, said Dale E. Kildee, D-Mich., who chairs the House Education and Labor subcommittee with jurisdiction over the reauthorization.

“I think she can play a significant role. She’s respected on both sides of the aisle. [Mrs. Bush] probably can move them toward getting a majority of the minority.”