Remember the "gender gap"?

The last presidential campaign was full of stories about women voters' supposed dislike of the Republicans.Ronald Reagan ended up with landslides among both sexes, but with a closer election expected this year even a small gap could be decisive.

This time, however, analysts should focus on a less-publicized phenomenon: the marriage gap.

A recent essay by Bryce Christensen of the Rockford Institute Center on the Family in America notes that differences betweeen married and unmarried voters are far wider than generally realized.

Christensen cites surveys showing that Reagan was the choice of 63 percent of married voters in 1984, but of only 45 percent of never-married voters.

A study by sociologists at the University of Virginia found this difference "largely similar throughout the population," not confined to particular ethnic or income groups.

This marriage gap was not new. A 1983 study found married women more pro-Reagan than single men.

If only singles had voted in the 1982 House elections, "the Democrats might easily have gained 60 seats instead of 26. On the other hand, if only the married had voted, Republicans would very likely have held their ground or even gained."

Why such dramatic differences? One reason is economic: Intact families are far less dependent on government subsidies than broken ones.

About three-fifths of illegitimate children are on welfare, compared with one-third of children of divorced mothers and only one-tenth of those in married-couple households.

Two Stanford economists suggest that for unmarried mothers Washington has become "the marriage partner of last resort" a polygamous provider whose millions of "wives" vote for big-government politicians.

More profound are the cultural and moral differences.

Married couples are less permissive than singles about drug use and adolescent sex, harder-working, more active in groups such as churches and scout troops, and less sympathetic to special privileges for homosexuals. Once they have children they become even more traditionalist.

Most American voters are married and many of the rest would like to be. If the Democrats stay on the wrong side of the marriage gap they may find that victory is more elusive than they think.