How much will the 1984 elections settle? It would be nice to think that a long, drawn-out election like the one now ending could reward our pain with a successful new political and economic era. That could prove to be the case, of course, if Ronald Reagan's near-certain victory can yield the fruits he promises.
On the other hand, there are reasons for skepticism and for concern that the fuller resolution of America's future may have to await the election of 1988, the first occasion since 1960 when both parties know in advance they'll be nominating nonincumbents. That could well be the watershed event. We don't have many ''double vacancy'' elections, but somehow they've signaled major directional changes. Perhaps the process of both parties picking nonincumbent presidential nominees generates an unusual number of new ideas and helps clean out intellectual cobwebs.
By contrast, reelection of a president to a second term involves further movement in existing directions, coupled with a midterm loss of momentum. And Reagan, of course, is already our oldest President.
Let us clarify that the prospect of President Reagan's winning reelection by a landslide doesn't necessarily mean much in itself. Remember that the last three presidents to be put back in office by landslides - Dwight Eisenhower in 1956, Lyndon Johnson in 1964 and Richard Nixon in 1972 - found these new terms less successful than expected. Two were directly or indirectly driven from office (Nixon and Johnson). And all three saw their parties experience heavy and debilitating losses in the midterm elections.
Which brings me to another weakness of second-term presidencies. Over the last half century, US voters have invariably found themselves beginning to sour on administrations after six years. Analysts call this pattern the ''six-year itch,'' and because of it, the party in the White House has lost heavily in both houses of Congress. Congressional losses by the party in the White House Year/President/Party House Senate 1938 (Roosevelt - Democrats) -70 -7 1958 (Eisenhower - Republicans) -47 -13 1966 (Kennedy/Johnson - Democrats) -48 -4 1974 (Nixon/Ford - Republicans) -48 -5 1986 (Reagan - Republicans) ?? ??
Repetition of this loss pattern in 1986 would not be surprising. Republican vulnerability would be greatest in the Senate, where 22 of the 34 senators up for reelection will be Republicans, not a few of them little-known individuals lucky enough to ride President Reagan's coattails in 1980. So in 1986 it's already reasonable to forecast that the Democrats have a good chance to recapture the Senate and strengthen their majority in the House.
Unfortunately for the Republicans, a second potentially troublesome pattern will also haunt a second Reagan administration. Whereas the Democrats have usually been the party presiding over serious 20th-century accelerations of inflation, the GOP has had more than its share of recessions.
In fact, the last five Republican administrations have all presided over midterm recessions, each downturn coming just in time to help dissipate the favorable trends set in motion by the dynamics of the preceding presidential election. Thus the recessions of 1954, 1958, 1970, 1974 and 1982 all put off GOP realignment ambitions. Looking to the future, the recession that most economists seem to expect by 1986 could do the same, casting renewed doubt on the effectiveness and durability of Reaganomics. Because belief in the Reagan administration rose and fell with the economy in 1981-84, it could do so again in 1985-88.
What's more, if the Republican election-economic cycle plays itself out in the postwar manner, the 1983-84 recovery (and its extension into 1985) will be remembered as the mountain between two recessionary valleys: on one side, the recession of 1981-82; on the other slope, the downturn expected by 1986. Precisely this happened under both Eisenhower and Nixon; the business cycle conveniently peaked more or less around the time of the 1956 and 1972 presidential elections, but then slipped toward recession again. If postwar Republican administrations have been reasonably agile in targeting prosperity on presidential reelection years, they have been much less successful in scripting the sort of spreading, deepening long-term prosperity the Reagan administration now promises.
Overall, then, there are a lot of reasons to doubt that a second Reagan administration can be the success story it hopes. To be sure, Republican strategists argue that the GOP is shedding yesteryear's austerity and recession economics, embracing instead what they call a ''conservative opportunity society ,'' so perhaps a second Reagan administration may be able to transcend the political and economic precedents cited above. If not, however, there's a good chance that within a year or two, a growing number of Americans will begin to find themselves focusing hopefully on the election and opportunity of 1988.