Washington ? Struggling to finish a politically thorny task, the base-closing commission tackled a shake-up of the Air National Guard on Friday after – in a setback for the Pentagon – it voted to keep open Ellsworth Air Force Base in South Dakota.

The nine-member panel endorsed the concept of restructuring the Air Guard but did not accept Defense Secretary Donald H. Rumsfeld’s proposal in its entirety. Instead, commissioners began to craft their own plan to shuffle personnel and aircraft around dozens of units – both large and small – in states from coast to coast.

“In parts, we concur with their recommendations. In other areas, we’re making some changes,” Chairman Anthony Principi said.

The commissioners planned to work into the night to conclude the high-stakes decisions in the first round of U.S. military base closings and consolidations in a decade. The process has brought sighs of relief and exasperation from communities across America.

By Sept. 8, the panel must send its final report to President Bush, who can accept it, reject it or send it back for revisions. Congress also will have a chance to veto the plan in its entirety, but it has not taken that step in four previous rounds of base closings. If ultimately approved, the changes would occur over the next six years.

Airman First Class Earvin Larry, left, and Airman First Class Daniel Osorio perform maintenance on the wing of a C-130 at Dyess Air Force Base in Abilene, Texas Friday. The Base Closure and Realignment Commission voted Friday to keep Dyess and its fleet of C-130s intact. The commission also rejected a Pentagon plan to move B-1 bombers now stationed in South Dakota to Dyess.

Air Force officials say their proposal as a whole is designed to make the service more effective by consolidating weapons systems and personnel while moving to a smaller but smarter fleet.

The Air Guard restructuring, which called for some units to lose their flying missions, has caused the most consternation and prompted some states to file lawsuits.

Under the Pentagon plan, units without aircraft would get other assignments such as expeditionary combat support roles. They also would retain their missions of aiding governors during statewide emergencies.

Work began on the Air Guard plan just as a federal judge in Pennsylvania ruled that the Pentagon lacks the authority to close an Air Guard unit located at the Naval Air Station Willow Grove in Pennsylvania without Gov. Ed Rendell’s approval. The judge declared the plan for that unit “null and void.”

Aware of the ruling, the commission labored on anyway – and twice voted on the fate of the Naval Air Station Willow Grove. Ultimately, the panel decided to close the base, but keep intact the Air Guard unit that was subject to the lawsuit and create an Army Guard and Reserve center. However, that unit would exist without aircraft.

Commissioners denied the lawsuit affected their ruling.

In a flurry of other Air Guard decisions, the commission sided with the Pentagon in voting to shut down the Kulis Air Guard Station in Alaska. The panel also chose to scale back – but keep open – the W.K. Kellogg Airport Air Guard Station in Michigan, rejecting the Pentagon’s closure recommendation. However, commissioners took away the aircraft there and gave the state the authority to decide the future use of the base.

In May, the Pentagon proposed closing or consolidating a record 62 major military bases and 775 smaller installations to save $48.8 billion over 20 years, make the services more efficient and reposition the armed forces. The Air Guard proposal emerged quickly as the most contentious issue.

The decision to spare Ellsworth Air Force Base was a blessing for South Dakotans, who feared losing some 4,000 jobs, and a victory for Sen. John Thune and the state’s other politicians, who lobbied vigorously against closure. Thune, a freshman Republican, unseated then-Senate Minority Leader Tom Daschle partly on the strength of his claim that he would be better positioned to help save the base.

“This fight was not about me,” Thune said just after the vote. “This whole decision was about the merits. It had nothing to do with the politics.”