The budget battle between congressional Democrats and the White House won't stop the proposed January pay raise for white-collar federal workers, but it could mean furloughs and/or layoffs this year and next in some agencies.

President Reagan has proposed a 2 percent January pay raise, but Congress may raise that to 3 percent.

However, congressional Democrats are seeking about $12 billion in tax increases, and reduced defense spending, as an alterative to automatic cuts waiting in the wings because of the Gramm-Rudman-Hollings deficit reduction law. The president opposes tax increases and defense spending cuts, and there is growing speculation that he might call the congressional bluff and let the $23 billion in across-the-board cuts required by the deficit reduction law take effect. Whether that will happen is anybody's guess, because even the most devout budget cutters prefer selective cuts to across-the-board slashes.

If the stalemate continues it could, however, block the higher federal pay raise Congress is considering. It also could force agencies to scramble to make immediate cuts, in people and programs, even as they prepare to implement a billion-dollar-plus pay raise in January.

If reductions-in-force become a reality, some agencies would move to fire employes as quickly as possible after the fiscal year begins to save the maximum amount of money.

If layoffs occur, that could be a shot in the arm for the early-out retirement plan proposed by Sen. William V. Roth Jr. (R-Del.). His bill would let hundreds of thousands of U.S. workers take early retirement (on smaller pensions). It has been blocked by federal employe unions. They argue that the Roth plan would cause a brain drain and leave the government understaffed while opening the door to private contractors to take over work now done by civil servants. But if the layoffs are imminent, legislators who have opposed the early-out bill could see it as the lesser of two evils.

Bill Watch

The House Post Office-Civil Service Committee is expected to approve legislation today that would liberalize the Hatch "no politics" Act. Under the proposal, by Rep. William Clay (D-Mo.), federal and postal employes would be allowed to take active roles -- as candidates, campaign managers or fund-raisers -- in partisan political campaigns, provided they did so off duty.

Clay's bill already has more than a hundred cosponsors, and the House is expected to give it quick approval, although the Senate may not clear the bill until early next year.

The House committee also is expected to clear bills that would pave the way for rehiring of some air traffic controllers fired in 1981 for taking part in an illegal strike, and to make technical amendments in the new Federal Employees Retirement System.

Meantime, the Senate has passed and sent to the president legislation that would mean pay raises for Library of Congress police officers. The bill, sponsored by Rep. Mary Rose Oakar (D-Ohio), would give those Library employes the same (higher) pay rates as U.S. Capitol Police personnel.

Drug Testing

National Treasury Employees Union President Robert Tobias will talk at this morning's "newsmakers" program at the National Press Club about his union's efforts to block mandatory drug testing.