Mike Isikoff's pudgy face wore a bemused smile as he prowled the press gallery, searching for an open telephone. He found one eventually and made a quick call: when he hung up the little smile had turned into a large grin. Mike Isikoff. Washington correspondent was onto a good story.

It was doubly sweet. Good stories were rare enough any time on Isikoffs rather mundane beat. But to find one now - it was the end of last July - was a particular boon, because Isikoff had been expecting nothing but drudgery.

For days Isikoff had been sitting in the press gallery as the House droned through debate on the omnibus farm bill. It was important news for the six downstate Illinois newspapers he represented, but Isikoff himself a product of the Long Island suburbs, was finding the farm story less than enthralling.

Until he noticed something funny about George Shipley.

Shipley is the Democratic congressman from Illinois' 22nd District a sprawling chunk of territory in the east central section of the state. The 22nd is 90 percent farmland and the farm bill is probably the most important legislation in Congress for Shipley's constitutents. And that's what was funny: Shipley had missed every vote on the farm bill.

Isikoff's discovery of Shipley's missed votes, and the congressman's explanation for them, blossomed into a news story that deeply embarrassed George Shipley. With some help from Gene Stunkel, a hard-charging fast food proprietor in Shipley's district, Isikoff followed up with more embarrassing stories. Within a few weeks, the 50-year-old congressman, a veteran of 10 House terms, announced he would not seek reelection in 1978.

Shipley's surprise withdrawal - he had seemed a safe bet for another five or more terms in Congress - drew three Republicans and four Democrats into a wide-open race for the seat, giving the 22nd what could become one of this year's tightest congressional contests.

All in all, at turned out to be one of the best stories Mike Isikoff had produced as a Washington correspondent, "Washington correspondent" - it had seemed an awfully glamorous title in 1976 when Isikoff, fresh out of journalism school, landed a news service job covering the capital for medium-sized newspapers around the country.

But the newcomer learned quickly that the glamor of Washington reporting - briefings at the White House, "business lunches" at expensive restaurants - was not to be his. About three-quaters of the 1,200 newspaper correspondents in Washington deal strictly with regional news, and Isikoff joined that majority.

When the Dan Rathers and James Restons came to the Capitol to cover the State of the Union message, Mike Isikoff was there too - but he was scurrying after what the trade called a "local react" story ("Downstate solons reacted along party lines to the President's call for . . ."). When the major environmental reporters searched for the big policy shifts in the Clean Water Act, Isikoff was probing the fine print in committee reports to see if the Alton Box Board Co. would get an extension on meeting emission standards (the Illinois firm did, giving Isikoff a banner front page story in the Alton Telegraph).

"Find the local angle" was the name of the game, and Isikoff, with a quick mind and an unending reserve of youthful energy, played it better than most.

But the front page banners didn't come often: they couldn't given his standard assignment, which was to follow the daily business of the congressmen from the seven districts his papers covered Isikoff's congressmen - "my turkeys," he called them affectionaly - were just not newsworthy. And the least newsworthy was George Shipley.

Whatever else people may have said about George Shipley during his 20 years in Congress, it seems safe to assume that no one has ever accused him of being newsworthy. An elusive, white-haired gentleman of mild voice and moderate demeanor, he is a figure easily lost among the swarms of loudmouths and glad-handers that populate Capitol Hill.

Although Shipley has never pursued any key investigation or sponsored any major legislation, the congressman has one redeeming virtue that won him praise from both colleagues and constituents: he was a truly nice guy.

"George is as common as common can be," observed his brother-in-law and administrative aide, Don Watson. "He's as nice as the day is long."

Shipley's human qualities impressed on the 22nd's voters through thousands of trips home over the years, had enabled him to turn teh district into a safe seat - a considerable achievement for any Democrat in downstate Illinois.

Shipley had proved that in 1970, when Republicans recruited a homegrown national heroine of the right - Phyllis Schlafly - to challenge him in the confrontation with 54 per cent of the vote. By the 1976 election. Shipley had built his victory majority up to 61 per cent.

With electoral success assured, George Shipley began to think about a goal he had not previously dared to dream of: chairmanship of the House Appropriations Committee. By the end of the 95th Congress, he would be sixth in seniority among committee Democrats. If his health held out (he had been plagued by a recurring backache), Shipley might easily, in five more terms or so, succeed to the chair of one of the most powerful bodies in Congress.

For the moment, though, Shipley was attending to more immediate concerns: serving constituents, and voting as they wished him to on the bills they cared about.

Among the bills that downstate Illinois cares most about is the omnibus farm bill, the basic authorizing legislation for price supports and other aspects of federal agricultural policy. Thus when the farm bill came up for debate in the House late last July, a host of correspondents for farm state newspapers was ensconced in the press gallery. Among them was Mike Isikoff.

As each new amendment came up for vote, Isikoff would shuffle through his growing pile of notes to find the tally sheet on which he was tracking votes of the seven congressmen he covered. With the confusion of taking constant notes and meeting constant deadlines, it was a few days before Isikoff noticed something funny - he had no record of votes by George Shipley.

Isikoff quickly placed a call to Shipley's office, and learned that his tally sheet was right: Shipley had missed every vote on a bill of utmost importance to his district.

Isikoff grinned the grin of a reporter who has found an exclusive. Then he set out to build his story. Burrowing through back issues of Congressional Quarterly, the reporter discovered Shipley had voted on 89 per cent of the calls in 1976 - about average for House members. Then Isikoff worked through recent copies of the Congressional Record to check roll calls in July 1977 and found a striking difference: in the past month, Shipley had missed two-thirds of the votes.

Tat was a fairly hot news item itself, but when Isikoff tracked down the congressman to ask what was going on, the unwitting Shipley turned a good story into a better one.

"My back hurts, Mike," the congressman said. "It's bad. Sometimes it hurts so bad I just have to stay in bed."

But the congressman said he really didn't want to talk about his health problem. "Everybody here knows I've got it," Shipley explained. "But the folks back home don't know about it - and I don't want them to know."

Isikoff's resulting story created a mild uproar in the 22nd. It was not the missed votes that bothered people: it was the notion that Shipley was hiding facts about his health problem. "You can't help but wonder," the Decatur Herald said in an editorial, "what else Rep. Shipley does in Washington that he doesn't want folks back home to know."

Mike Isikoff was still savoring his scoop two days later when a ringing telephone brought him out of his reveries. "You really blew it on Shipley," the caller snapped."Yeah, there was a much bigger story than the one you got, but you really blew it."

Isikoff did not know it, but the mysterious caller was Gene Stunkel, a successful businessman - he was proprietor of among other things, a fast food chain called "Genie's Wienies" in Danville, III., largest city in the 22nd district. Stunkel had decided, a few months before, to run against Shipley in 1978. He wanted to give Isikoff a tip that could embarrass the incumbent.

"You say Shipley had such a bad backache he had to stay in bed last week?" Stunkel asked. "Then how come he was at a golf outing out here last Friday."

At first, Isikoff didn't believe it. Some of his congressmen told him lies from time to time, But Shipley had always been straight with him. A little checking proved the tip was right. On July 29, When the farm bill had been up for final action on the House floor. George Shipley was at the Quail Creek Country Club in Robinson, III., hosting a golf tournament and dinner to raise funds for his 1978 campaign.

"Shipley Attended Fund-Raiser While Too Sicj to Vote in House," shouted teh headline over Isikoff's story in the Decatur Herald. Even Isikoff's competitors had to pick it up, and then the radio stations did, too. Soon the great story was all over Illionis.

For George Shipley, it was a blow. The papers had always been decent to him, and now this. When Congress recessed in August, Shipley went alone to a Florida retreat to think things over.

"Ah, hell, I would've loved to become chairman of appropriations."

Shipley said not long recalling his Florida ruminations. "And I liked the job. I had those friends all over the district met 'em through this job.

"But still, I had been thinking about getting out since after the '76 election. My back really hurts sometimes, and this job - you're sitting in a chair all day - doesn't go for a man with a back problem. I could've had an operation, but I'm scared of it. And now my back's in the newspapers out there."

After a week of thought, Shipley placed a call to brother-in-law Watson: "Don," he said, "I'm getting out. It's all yours if you want to run."

While Shipley had decided to leave from the House, he wanted to keep the seat in the family. So he offered the chance to Watson, who accepted. In the press release in which he announced his withdrawal, George Shipley endorsed his brother-in-law in the March 21 congressional primary. That made Watson the early favorite in the Democratic race.

And it posed a quandary for the other candidates in both parties. Should they, too seek endorsements from prominent allies? And would any endorsement be as fruitful in the 22nd as George Shipley's? It was a trying problem . . .