As Advocates of the somewhat unorthodox notion that winning is coming in first in elections, we note at the outset the conspicuous truth that both President Carter and former ambassador George Bush scored impressive victories in the Iowa presidential caucuses on Monday night.

For the two earlier favorites in their respective parties, Sen. Edward Kennedy and former California govenor Ronald Reagan, Iowa was a major setback. Mr. Reagan was criticized for ducking the Des Moines Register's Republican debate, and apparently he suffered from comparison with Mr. Bush's very effective personal campaigning. For Sen. Kennedy (and for most people in the political world), it was not the totally unexpected defeat at the hands of President Carter, but rather the crushingly decisive margin of the Carter victory. By his own admission, Sen. Kennedy must win in his native New England to keep his struggling candidacy alive.

What stands out as much as the size and dimension of the Carter and Bush triumphs is the arithmetic of the Iowa evening. In 1976, the Democrtic and Republican caucuses, combined, drew approximately 60,000 voters. Monday night, close to 225,000 Iowans participated in their precinct caucuses. Apathy and indifference were nowhere to be found in Iowa on Monday. And let us understand what participation, in fact, required. The polls were not open for 12 hours. In order to play any part, the voter had to show up at the designated school, library, or church at 8:00 p.m. If the voter had not arrived by 8:30, his or her preference was not recorded. The very unprivate nature of the process was another inhibiting factor. There were no voting booths with curtains to preserve anonymity in any Iowa caucus. In front of friends, spouses and even bosses, voters at the caucus had to stand up and publicly declare their support for a presidential candidate. That can make an awful lot of people understandably uncomfortable.

Yet in spite of the obstacles of season, scheduling and public discloure, considerably more than three times as many Iowans spent a couple of hours registering their support for their choice, this year, than did four years ago. Undoubtedly, more candidates spent more time and more money in Iowa, this time, and there was more reporting on the state by print and broadcast journalists. All of this presumably helped to increase both interest and turnout. But credit must fairly go to the Iowa voters who demonstrated their concern and their willingness to commit in impressively encouraging numbers. Let us hope that voters in the states that follow will demonstrate similar enthusiasm and seriousness.