YOU DON'T HAVE to know the winner of the presidential election to predict that every other political analyst on the day after will find some reason to cite -- recite for the umpteenth time, really -- voter "apathy" as a factor in whatever result is under analysis. In many instances, the critiques will treat all no-shows as somehow anti-American or derelict in fulfilling some "duty" as citizens. And if the decision is close, the non-voters will be upgraded from "factor" to "critical factor" in the results.

There is such a thing as the freedom not to vote. People who don't like any candidate or don't care who wins are free to ignore the process. But in the next few days, many people who may want to vote -- or at least to preserve the option -- may be dealt out of the election because they failed to register. t

To be specific, if you live in Virginia, today is the deadline for anyone not already registered to vote in the state. District and Maryland residents have until the close of business on Monday to get on the rolls. In most cases, public libraries are handling the job over the weekend, or can direct callers to the right places. The best up-to-date, 24-hour information service is in Montgomery County (424-4433) and Prince George's (627-2811). But throughout the region, the procedures are much simplier than they once were.

Over the years, residency requirements have been shortened, as has the amount of time between registration deadlines and elections. Postcard registration and improved ways of purging voter rolls also have simplified the process. So the old excuses about being disenfranchised by complicated registration rules and early deadlines don't really wash. The point is that the first election decision for many people is now not Nov. 4.