Metropolitan Washington's $800 million-a-month federal payroll--it covers everybody from the president to the Washington Monument's elevator operator--may get its annual October transfusion despite administration attempts to keep the lid on government pay.

Both the Senate and the House have tentatively rejected the president's request to skip the 1983 federal pay raise.

The House has approved a Democratic version of the budget. It calls for a 4 percent pay raise this October for most of the government's 1.3 million white-collar civilians, including 300,000 here.

The Republican-run Senate Budget Committee has also voted its own spending measure for the fiscal year starting in October. It too provides for a 4 percent federal pay raise.

Although neither budget deals with the nearly half-million wage board (blue-collar) civil servants who are paid under a different system, they would probably get the same raise as their white-collar counterparts--if there is a raise.

The issue isn't out of the legislative-political woods yet. President Reagan still has time to persuade Congress to go along with his proposal of no pay raise this year. If that fails he can, under the current federal pay-setting law, force Congress to vote separately on the pay issue in late August or early September.

The administration's hopes for blocking any pay raise lie in the Senate, which is controlled by the president's own party. But he could have some defections on this issue.

One of the Senate votes the president will probably lose is a key one, belonging to Ted Stevens of Alaska. He is the Senate's assistant majority leader. Equally important, he is up for reelection in 1984.

The last time Stevens ran he got 72 percent of the 110,000 votes cast. Nearly 19,000 Alaskans work for Uncle Sam (plus another 23,000 military personnel) and have a significant interest in the pay raise.

The administration is also likely to lose several other Republicans, namely Sens. John Warner and Paul Trible, on the pay issue. There are 140,000 federal employes in Virginia, and all of them are old enough to vote.

So, while it is still too early to rejoice for a pay raise (or for landlords to raise the rent or parking lot owners to adjust their fees) things are looking up for the feds.