Washington — The Illinois primary gave many signs that US political life continues to churn.
In the first official changing of the guard in the 1982 political year -- in the Illinois primary March 16 -- at least three US congressmen stepped out of the broad ranks of 406 incumbents nationwide seeking reelection.
Illinois's losses among incumbents -- two Republicans, at least one Democrat, with another Democrat tottering at latest count and another GOP member squeezed out by redistricting earlier -- make up a fifth of the state's Washington delegation. This suggests that officeholders in both parties face considerable political risks this year.
The balloting also showed that Chicago's once-formidable Democratic machine continues to sputter and slip cogs. Chicago Mayor Jane Byrne and state's attorney Richard M. Daley, son of the late ''boss'' Mayor Richard J. Daley, continued their feud to control Cook County -- Chicago political turf. Mr. Daley won a round in unseating Chicago incumbent Rep. John G. Fary by backing the victor, Alderman William O. Lipinski, a Byrne foe. Mrs. Byrne tried to unseat black Democratic incumbent Rep. Gus Savage, a south Chicago freshman with the worst attendance record in Congress last year.
In the governor's race, GOP incumbent Gov. James R. Thompson and former US Sen. Adlai E. Stevenson III won, as expected, the right to a tug of war over the scant 9 points that polls say separate them.
From a national perspective, the Illinois outcome at all levels is significant:
* In the House races, the GOP's first losses this year are among moderates, the faction the President's party must depend upon to forge a coalition with Democrats in domestic politics.
* The further decline of the Democratic machine suggests still less of a national role for the party and its power brokers, and less effective control by the city of its own political affairs as power switches to the statehouse.
* And in the governor's race, a jeopardized GOP base in Illinois would continue the tilt of the Midwest from the bastion of Republican gubernatorial power to one of the party's weakest regions in a single election. GOP governors in Michigan, Ohio, and Iowa are leaving office this year, and Minnesota and Wisconsin's GOP-held governorships are threatened.
Ideologically, moderate GOP ranks in Illinois have now lost two key members.
Rep. Tom Railsback was defeated Tuesday. He is considered a moderate GOP bridge-builder between right and left factions of both parties on the House Judiciary Committee. Congressman Railsback was beaten by New Right activist Kenneth G. McMillan, a rural conservative who favors prayer in public schools and capital punishment and opposes gun control, abortion, and the equal rights amendment.
Earlier, another senior Illinois congressman, Rep. Robert McClory, bowed out of the race. Congressman McClory, a respected member of the House, would have chaired the House Judiciary Committee if the GOP won House control this year. He refused to stand for reelection because redistricting would have pitted him against Republican colleague John E. Porter along Chicago's north shore.
Redistricting favors the Democrats in Illinois congressional races this year. The two House seats the state will lose will likely come from Republican ranks, with possibly a third GOP seat lost as the courts protected black Chicago seats.
But the Democrats in Illinois still have trouble, beginning with their candidate for governor.
''Stevenson's running a peculiar kind of campaign,'' observes Milton Rakove, an Illinois political writer. ''It's offbeat. He's not going to spend a lot of money, or raise a lot of money. He's had some troubles with Jews -- his record in the Senate on Israel is not that good. His relations with labor aren't that good. None of the (Chicago) ward Committeemen really supported his fund-raising dinner. My guess is they won't work for him.''
The Chicago area, wmth 7 million of the state's 11 million population, is the key arena in Illinois politics. Big Chicago margins are necessary for Democrats to offset GOP suburban and ''downstate'' strength.
But the Democratic machine is sputtering.
''The machine is so weak these days,'' says Rakove, the principal historian of the Daley and Byrne mayoral years. ''There's tremendous apathy,'' he says of Illinois voters generally. ''The voters aren't interested in Stevenson. And they're not too happy with Thompson. They think he's fronting for Reagan.''
Stevenson must walk a tightrope between the Chicago factions headed by Mayor Byrne and the late Mayor Daley's son, Richard. Mrs. Byrne has said she would support the candidate of the party, but she was in Palm Springs during Stevenson's recent Chicago fund-raiser.
Another part of the Byrne-Stevenson friction is in their attitudes toward Reagan programs. While Stevenson attacks Reagan's ''new federalism,'' Mrs. Byrne is trying to be friendly toward Reagan economics so she can remain on good terms with federal agencies.
Also, in Chicago's perverse manner of turf protection, Mrs. Byrne probably prefers to have Republican Thompson in Springfield rather than a Democrat. This helps keep Cook County the primay seat of Democratic power in Illinois.
Governor Thompson's handlers say that the governor's nine-point lead over Stevenson looks great.
He's had to propose an austere budget,'' says David Gilbert, Thompson's spokesman. ''He's had to close three mental health clinics, with substantial job losses for those communities. He's cut aid to education, closed the institute for visually handicapped in Chicago. It's hard to have a chicken in every pot. Yet Illinois is the only Northern industrial state with a triple-A bond rating. Illinois is not like Minnesota (under the recent economic stresses). Minnesota sank like a rock. Illinois is still floating.''
Nonetheless, some Republican officials in Illinois worry that prolonged economic slump could turn into a general anti-incumbent sentiment among voters, and that Stevenson's sleeping campaign could awaken the party faithful or attract independents. Independents make up about 42 percent of Illinois voters, with the Democrats holding 34 percent, and the Republicans 24 percent.