It was like a cocktail party in Hell, One hundred reporters and one Radcliffe extern had been waiting for half-an-hour in the end of a corridor intersecting President Reagan's route to the old Senate chamber. There, he planned to lobby 13 recalcitrant Republicans who had voted to override his veto of the $87.9 billion highway bill. We hoped he would conclude his mission before lunchtime.

Usually there was nothing to see, except for a mass of highly trained adults, covering one of their profession's most coveted assignments, shifting their weight and waiting for the President like courtiers. All this for a simple TV visual or possibly and answer to a single question.

The "stakeout" had begun at 11;00 on Thursday morning, the third day of maneuvering in the Senate over HR 2, an untidy, bloated package of $87.9 billion in transportation funds, with an increase in the speed limit tacked on to attract Western legislators' support. Rhetoric aside, nobody cared what was in the bill by now, and few had even read its entire convoluted text.

What mattered was that the president had vetoed the bill, and the Republican leadership had spent the past week telling the press that his ability to keep Congress form enacting it would be a crucial test of Presidential power."

Practically, this meant that if both legislative bodies could not find the two-thirds majorities necessary to override the veto, Reagan would take this as a sign that he retained enough of his waning power to continue vetoing bills throughout the summer.

when the President finally arrived, fierce whispers urged those in front of the camera emplacements to duck below the lenses, so that Reagan saw a tired crowd, half of them kneeling before him in the white brilliant light that he loves. "Mr. President," bellowed a television reporter, "Do you think you can change a vote around? "His voice echoed in the mosaic hallway. The president of the United States, preoccupied and confused, failed to react, then shrugged expressively when the question was repeated.

HR 2 had one powerful argument in its favor--greed. Each Senator, regardless of party principles, contemplated the healthy re-election margin that an electorate well-greased with Federal funding would produce. Every part of the country needed jobs and contracts. Some even needed highways. The bill was a good example of pleasing most of the people most of the time.

Two days before the stakeout, the House of Representatives had voted 350 to 73 to override the veto--far exceeding the required two-thirds majority. Now the override depended on two-thirds of the 100 Senators. Majority Leader Robert C. Byrd had to keep his troops disciplined; only 34 "no" votes could defeat the override.

With only 54 democratic Senators, Byrd had to keep 13 Republican away form their President by using the bill's carefully wrought generosity to large states with Republican delegates, such as Pennsylvania. The New York Times reporters said it was one of the few votes they had seen that was too close for even a hunch.

The press corps decided to wait out the President's session. By waylaying aides and Senators who emerged form the chamber, we learned that by the end of an hour, the President, the 13 rebels, Minority Leaders Robert Dole and Transportation Secretary Elizabeth H. Dole remined in Dole's office. A series of false alarms caused the TV technicians to turn on the bright lights from time to time and growl, "get down!" to reporters in front of the cameras, but none of the antagonists emerged.

They say the House's elegant mosaic floors are particularly hard and bad for the joints. And the slouching postures and shifting feet seemed to bear this out. Reporters spend a lot of time waiting, and those who cover Congress have learned to show docile patience.

Things have presumably become easier since the C-Span cable network began televising the proceedings of the two houses. Now reporters watch them on big television sets in the third-floor rabbit warren called the Senate Press Gallery, with its incongruously ornate ceiling and floor, joined by drab partitions of a later date. Where they once had to sit in the gallery, now correspondents can watch the action or lack thereof as they tap away at their modem word processors, sip coffee and turn down the volume on Senators D'Amato and Helms.

Chat filled up the time. One woman recounted the woes of a dreary day following her state's legislative delegation through a series of raucous St. Patrick's Day appearances. A fellow from a small wire service told a joke about the scandal surrounding Rev. Jim Bakker. "He's a lay preacher." "What?" "He got laid, get it>" It fell very flat among the correspondents' business suits.

Some toyed with the dog tags around their necks. Capitol ID cards for the press show the holder's picture with a motley background of red and yellow, divided diagonally. Correspondents with White House clearance badges wear them like epaulettes, letting the elaborate hologram in the ID's plastic cover catch the light.

Someone said the encampments outside Albany budget hearings lasted for days at a time. I looked at the ceiling and wondered whether this waiting game became bearable with practice. A camera technician pushed through the crowd with a folded tripod, muttering, "This is the limit. I'm getting my real estate license."