Tom Korologos, who probably deserved combat pay for his service as congressional lobbyist for Richard Nixon's White House, some time ago issued his own First Law: "Republicans are not fit to govern." The Senate vote supporting the president's decision to sell AWACS to Saudi Arabia may have effectively repealed Korologos' First Law. At least that's the hope of its author.

If that hope is to be realized, if the Republicans are actually about to become the party of governance, then Sen. Howard Baker rates several drum rolls and a couple of curtain calls. Baker seemed to understand, better and quicker than most, the adjustments required of Republican senators when they became the majority party within the chamber and had a president of their own party.

Discipline and cohesiveness are not strangers to most legislative minorities anywhere. Parties in opposition, unencumbered by collective responsibility for ultimate policy, rarely resist the temptations to take a cheap shot at the people in charge. But keeping a majority together is a lot more difficult. With power come parking spaces and accountability. On the showdown vote, thanks in no small part to the effectiveness of Baker, 41 of the Senate's 53 Republicans supported the president.

For Ronald Reagan, the AWACS victory was one more version of his Frank Merriwell triumphs on Capitol Hill. Like the fabled college athlete whose last-minute heroics always carried the day, the president overcame his team's early fumbles, inept scouting and lousy play-calling. In the end, Reagan appeared to act on the belief that political support is something a leader builds up rather than burns up; that political capital, to be of value to its holder, must be risked. Those are important messages for any chief executive to deliver to any Congress, anytime.

Because of White House and administration mistakes at one point, Baker had the committed votes (including his own) of only 13 senators on this difficult issue. But the Senate leader did not publicly groan about the ineptness that had left him with this Baker's dozen to lead. No anguish was heard in his voice; there was none of the martyr in his manner.

Throughout the contest, he was both cool and steady. On an issue where passions ran only high and higher, Baker was a moderate man, understanding that legislative politics is always a matter of addition, not subtraction. His approach seemed to be: how can we make it easier for you to be with the president? He sternly reminded his Republican colleagues that they had a responsibility to suport the Republican president. But he never scolded.

As is always the case after such Senate votes, the vanquished expressed shock about pressure tactics and presidential arm-twisting. It's pretty simple: when my guy in the White House uses such means, it's skillful presidential leadership; when your guy does it, it's an outrage and bordering upon bribery.

In lobbying, the most difficult of all tasks is to persuade any legislator to change positions on an issue publicly. Switches anger partisans on both sides of any question and communicate a legislator's impotent indecisiveness to everybody else who may be looking. But a lot of Republican senators, with Ronald Reagan making the case and Howard Baker making it easy, did just that. Their votes made the difference, and they may turn out to have made a majority as well.

The president is by no means assured of success in upcoming budget and appropriations battles as a consequence of what happened on AWACS. But with a defeat on the planes sale, the future battles would have been a lot tougher. If the Republicans in the Senate do become, sometime soon, a functioning legislative majority working with a Republican president, then Howard Baker, more than anybody else, will have repealed Korologos' First Law.