Washington — The presidency is not on the line. It is not a make-or-break election. Whatever the outcome, there's not likely to be a major change of course for the government.
This is the view of top-level officials of both parties on the eve of the voting.
''There will be no turning away from the Reagan themes,'' the former Democratic national chairman, Robert Strauss, told this newspaper. ''There will be no visible pulling back from the public's desire to get government off its back - or of wanting less government.''
The President himself is portrayed by White House insiders as seeing this election, in the long term, as little more than a minor occurrence. They say he foresees a decade or more of ''governance'' by those who enunciate less-big-government themes.
Democratic leaders say that at most they might be able to achieve enough congressional wins on Tuesday to slow down the Reagan thrust.
Mr. Strauss says he believes, however, that the President's loss of credibility through election losses could be considerable. Others in his party concur with his assessment that many people ''are losing faith in the President's ability to do the things he said he would do.''
But these same Democrats, including Democratic national chairman Charles Manatt, still see the President as being politically very formidable - and likely to remain so - because of his personal appeal. That is why, during the campaign, Democrats have avoided any head-on attack on Mr. Reagan.
As a campaigner for others, the President, even in the view of his own people , hasn't been all that impressive. His ''stay the course'' slogan seems to have gone over best with those already determined to stay the course.
One prominent Republican, who asked not to be identified, says of the President's campaign strategy:
''His preparation was bad. Last spring he should have been telling the people that the economy was bad and likely to get worse. That unemployment would be getting worse. And so on. He should have gotten all the bad news out of the way then. Sure he would have taken some flak. But he would have it out of the way.'' He continued:
''Then this fall, on the campaign, Reagan could have gone on the offensive. Instead of conceding the problems now and having to defend his actions, which is a defensive and poor position, he could be lashing out at the Democrats and asking: 'Where are their alternatives?' And since they don't have any alternatives, he could have them on the run.''
Some Republicans also feel that the President made a mistake by involving himself so much in the election. But from within the White House comes this rebuttal from one key Reagan aide:
''The President is the head of his party and he should be out there; he should be involved. Further, I can't envision the people writing about the election not linking the result to the President whether he goes out or stays in the Rose Garden throughout the campaign.''
There is some worry in the Reagan camp that the election results could be quite bad - and that, despite the President's efforts to maintain popular support, his personal standing may take a decided dip.
Should this occur, one savvy Republican politician said, ''then this could make it most difficult for the President to pull his coalition together, even if he loses only a few House members in this election.
''House members are up for election, and they don't like to vote against a popular President, even if they are Democrats. But even Republicans may pull away from a President who no longer is all that popular.'' He continued:
''And even in the Senate, where the Republicans will likely keep control, a less-than-popular President may have difficulty holding the rather large number of Republican senators who are up for election in 1984.''
The prevailing view, however, from both the Reagan and Democratic camps, is that the President's popularity will remain intact, for the most part, after the election. This will enable him to govern, they say, even though he may have to make some concessions to Democrats in Congress.