Now will be the time when a theory of many political observers and political scientists will be put to the test. This is the view that divided government will once again make the presidency ineffective.
* Fact 1: This thesis did not prove out in Ronald Reagan's first term, despite a House nominally controlled by the Democrats. In the first two years the President fashioned a conservative coalition in the House that enabled him to place a highly visible Reagan stamp on legislation.
* Fact 2: The President's record landslide gives him a mandate - at the least , a personal mandate - to carry on. And he'll get his coalition in the House once again, despite talk from Democratic leaders that the GOP's pickup of seats falls short of that possibility.
A number of Democrats were running for election in the House who just squeezed through. As they contemplated a possible defeat, they readily reckoned what they had to do and say if elected. They are aware that should they buck Mr. Reagan and his conservative program, they will likely be singled out for political punishment in 1986.
In fact, many Democrats running for Congress and other public offices this fall began to sound like an echo of Reagan. They would drop their Democratic identification in political ads. They would conveniently forget to mention Walter Mondale and his tax-hike proposal.
In the waning days of the campaign, when an enormous Reagan victory was obviously on its way, I looked for reasons for the imminent landslide in grass-roots conversations with voters in Illinois. Was it simply personal adulation for Reagan? Or was there a conservative trend at work?
My conversations brought me to these conclusions:
1. Ronald Reagan has the type of personal appeal that elected Franklin Roosevelt again and again. But Roosevelt evoked dislike as well as veneration. Even those who were about to vote for Mondale were conceding that they ''liked'' Reagan and thought he was a ''nice man.''
2. But this Reagan appeal goes beyond just being liked. People trust him. They think he is honest and can be relied on when he says that he is seeking a lasting peace and that he will be able to improve the lot of all Americans.
3. But where Reagan really scores with the voters is with his talk about his long-held ideology.
There's simply a growing number of people, Democrats as well as Republicans, who are tired of paying taxes for government programs and who see in Reagan a President who will not add to this burden.
Mr. Reagan has also touched a particularly responsive chord when he talks about the crime issue and the need for society to be more attentive to the plight of the victim. So I'm convinced that this is the way Americans are feeling these days. More conservative? Not necessarily. But they do have deep anxieties which have caused them to turn to Reagan.
Are they part of a new GOP coalition? Again, not necessarily. Remember that millions of voters marked their ballot for Reagan and then moved over and voted for their Democratic congressional candidate.
But they did this with an implied warning, which goes like this: ''We expect you to help Reagan put through his program.'' Democratic congressmen know they defy such instructions at the risk of being rejected by these same voters in 1986.