Mario Cuomo probably had a tougher time defeating Edward Koch in the New York Democratic primary for governor than he'll have against Republican Lewis Lehrman in the November election.
That is the view of most political observers in New York State contacted by the Monitor following the Sept. 23 primary. Lieutenant Governor Cuomo pulled off perhaps the major surprise of the primary season by rolling up a 53-to-47 percent victory over the popular and colorful New York City mayor.
Already Cuomo has promised to use the fall campaign to rebuild the state's Democratic Party as an instrument of liberal social policies. And he would appear to be in an ideal position to do so. He scored well across the state, particularly in New York City, and emerged from the campaign unscathed personally or politically. Even Mayor Koch has pledged his support.
Moreover, the presence of US Sen. Daniel Moynihan at the top of the Democratic ticket should be of immeasurable help to Cuomo. Senator Moynihan coasted to victory in his race for renomination against a little-known opponent and likes to proclaim himself the ''most approved-of public figure'' in the state.
Cuomo, concludes Cornell University political scientist Theodore J. Lowi, ''will be a shoo-in.'' Only some late-breaking, damaging personal revelation about the Democratic nominee, Professor Lowi thinks, could deny Cuomo the governorship. But Cuomo, a former law professor, secretary of state, and candidate for mayor of New York, is by now well known to voters.
In complete candor, says Cuomo press secretary Gene Spagnoli, ''I would think it'll be easy.''
The Lehrman forces do not agree. Although they concede that the Republican primary fight against former US attorney Paul Curran - at a cost of about $7 million - was expensive, they also contend that their man is just as formidable a candidate as is Cuomo.
Mr. Lehrman - as his campaign field director, Tim Carey, points out - came from the back of the pack to claim the GOP nomination against a lineup of potential or actual candidates that included such heavy-hitters as US Rep. Jack Kemp, state comptroller Edward Regan, and Mr. Curran. In the process he rolled up 80 percent of the vote.
Moreover, the former head of an interstate discount drugstore chain is enlisting the aid of Vice-President George Bush and presidential adviser James Baker III, both of whom are scheduled to visit New York State in late October.
So far, one debate between Cuomo and Lehrman is scheduled: Oct. 7, in New York City.
The race, Professor Lowi thinks, will be hard fought - but on issues rather than on personality, as happened in the late stages of the Koch-Cuomo campaign, which was marked by bitterness. He says Cuomo would make a mistake if he tried to turn the campaign into a referendum on President Reagan.
Reaganomics, but not Reagan personally, will be a basic element of the Cuomo strategy, answers Mr. Spagnoli. ''Reagan,'' he says, ''is too nice a guy.''
Lehrman favors the death penalty, a phased eight-year cut in state income taxes, and opposes Westway, the huge and controversial New York City highway project. Cuomo opposes capital punishment, pledges not to raise the income tax, and favors Westway.
But Mayor Koch also favored the death penalty, Spagnoli notes, and yet it turned out to be less of an issue to voters in the primary than had been expected.
Koch, like most big-city mayors who seek statewide office, seemed to ''use up his base'' in the primary, Lowi says, winning by only a 51-to-49 percent margin in the city. The lone New York City mayor who successfully sought nomination to such office in recent times was Robert Wagner in 1965. But Mr. Wagner lost in his bid to unseat US Sen. Jacob Javits.