Campaign '80 in high gear now -- at 55 m.p.h.

The 55 m.p.h. speed limit may not decide the 1980 election, but there is no issue on which Democrats and Republicans are more sharply divided. Following condemnation of the speed limit in Ronald Reagan's Detroit platform , President Carter's Secretary of Transportation, Neil Goldschmidt, at a press conference here declared the limit is saving lives and energy. What's more, he said, "For the first time, more than half the nation's motorists are complying with it."

The GOP attacks so-called big government Democrats as interfering with individual freedom: "Republicans reject the elitist notion that Americans must be forced out of their cars," the platform says. It urges highway improvements to reduce fatalities that, it says, "may exceed 60,000 a year."

Secretary Goldschmidt, however, said the fatality figure is 45,000 annually. He declared that two years before the "55" rule, traffic fatalities averaged 54, 000 a year.

January-to-June statistics "show only 49 percent of motorists exceeding 55," Mr. Goldschmidt told a press conference here proudly. Since the 55 m.p.h. limit was introduced in 1973 "it has saved an estimated 37,500 lives," he declared.

Rival British and American claims to Oregon boundaries brought the slogan in the 1844 presidential election of "Fifty-four forty or fight"; the new controversy is "Fifty-five or fight."