Maryland Gov. Harry Hughes trounced two challengers in the Democratic primary yesterday, setting up what will likely be a much tougher general election race against Republican Robert A. Pascal, the Anne Arundel County executive, who also gained his party's nomination with minimal trouble.

Incumbent U.S. Sen. Paul S. Sarbanes and his Republican opponent, Prince George's County Executive Lawrence J. Hogan, also scored lopsided victories over a group of minor challengers.

Hughes, appearing at a victory celebration in Baltimore shortly after 11 p.m., said this primary victory was just as gratifying as his stunning upset of in the Democratic primary four years ago.

"It's a different feeling but still a very good one," the governor told several hundred supporters at the Lyric Theater. "Four years ago when the polls closed the professionals didn't think we would win. This time as an incumbent I was expected to win. The margin is gratifying."

With all but a handful of precincts reporting, Hughes had just under 350,000 votes, or 65 percent, compared to about 120,000 votes, or 22 percent, for Baltimore State Sen. Harry J. McGuirk. Ocean City Mayor Harry Kelley, the only other major challenger, pulled just under 59,000 votes or 11 percent.

Hughes said he expected both McGuirk and Kelley to lend their support to the Democratic slate in the general election. "Both these men have been friends of mine for a long time and I expect them to support me and the Democratic ticket," he said.

But by 11:30 p.m, Hughes had not heard from either of his vanquished opponents. McGuirk, who held a "victory" party at a south Baltimore restaurant, told reporters that he wasn't willing to conceded because "I want to talk to a couple of friends." However, just before midnight, after huddling with his running mate, Lt. Gov. Samuel W. Bogley, McGuirk acknowledged defeat.

"I feel we must concede the victory to Governor Hughes," the veteran legislator told his supporters to cries of "no, no, don't do it." McGuirk, who had been frustrated that Hughes did not take his candidacy seriously, refused to endorse Hughes, saying only, "I want to sit down with him and discuss the issues that should come into play in the general election."

McGuirk's loss also appears to end the improbable political career of Bogley, who catapulted from the Prince George's County Council to the statehouse with Hughes in 1978. While McGuirk left the headquarters to meet with Hughes, Bogley remained noncommital, although indicating he would support the Republican nominee in the general election.

"Before I commit to supporting Pascal I want to consult with some of the other Democrats who have been left out of the party's mainstream," he said. "I have indicated interest in Pascal in the past. I do not feel the same sense of comradeship and cooperation with the Democratic party that he McGuirk does. I do not feel an obligation to support the party's nominee."

Pascal, who also had a victory gathering in Baltimore, said he was looking forward to a hard-fought campaign against Hughes. The GOP nominee is expected to immediately begin his criticisms of Hughes in his effort to move from his county executive's office in Annapolis across the street to the Capitol.

Although yesterday's primaries yielded few major surprises, there were several notable exceptions.

In the 8th Congressional District Republican primary, former Montgomery County school board member Elizabeth C. Spencer defeated board member Marian Greenblatt.

Also in the Republican primary in Montgomery, banker Joseph C. McGrath defeated Del. Luiz R. Simmons and realtor John Hewitt for the nomination for county executive. McGrath will oppose incumbent Democrat Charles W. Gilchrist in November. In the Democratic primary, incumbent Montgomery council member Ruth Spector lost to former Rockville mayor William Hanna Jr.

In Prince George's County, incumbents fared even worse, setting up a dramatic realignment of the County Council. Three sitting council members, including Council Chairman Gerard T. McDonough, apparently were beaten. The defeats appeared to spell an end to a decade's dominance by a Democratic organization that was once considered one of the strongest in the state.

The elections also signal a realignment in the state legislature, where several prominent senators were beaten, most notably the minority leader, Republican Edward J. Mason of Cumberland. In another legislative race, former Baltimore County Executive Dale Anderson, who served 19 months in federal prison on corruption charges, won his Democratic primary, which in his heavily Democratic area is equivalent to winning the general election.

C.A. Porter Hopkins won the Republican nomination in the 1st Congressional District but only after a surprisingly close race with former congressman Robert E. Bauman, who dropped out of the race in July, too late for his name to be removed from the ballot.

In the contest for state's attorney in Baltimore city, challenger Kurt L. Schmoke defeated tough-talking incumbent William Swisher in the Democratic primary. The race between Schmoke, a black Rhodes scholar, and the organization-backed Swisher, was among the most fiercely contested in the state.

Although the day was clear and warm, state election officials reported that voter turnout was moderate, with a quiet morning turnout followed by final rush as the 8 p.m. poll closing approached. Election officials predicted a turnout of about 35 percent, a low figure attributed to the lack of hotly contested races.

Hughes dominated the gubernatorial race throughout the state. In the Washington suburbs, Hughes was swamping McGuirk. Montgomery figures showed the governor leading McGuirk by an 8-to-1 margin. In Prince George's County, where McGuirk had hoped the presence of Lt. Gov. Samuel W. Bogley of Bowie would hold down the margin, Hughes was leading by a 4-to-1 count.

Hughes ran very strong in Baltimore, on the Eastern Shore and in Baltimore and Howard counties. In Baltimore city, where McGuirk had hoped to overcome the governor's expected strong showing in the Washington suburbs, Hughes also had a comfortable lead. McGuirk campaign staffers had also hoped to do well, possibly win, in Anne Arundel, Pascal's area of strength, but Hughes took a 3-to-2 lead there.

Hughes's lopsided and expected win was in marked contrast to four years ago when he went into the primary a heavy underdog, expected to finish no better than third in a four-way race. His stunning victory on primary day over acting Gov. Blair Lee III was attributed largely to Hughes' promise to restore integrity to Maryland's scandal ridden state house, a theme he has harped on in this primary.

Ironically, one of those doing commentary on Hughes' victory last night was former governor Marvin Mandel, who was forced out of the state house after he was convicted of political corruption.

All three of the Democratic gubernatorial candidates spent the day trying to gather a few last second votes. Hughes, after voting in the Cross Keys section of Baltimore, where he lived before he was elected four years ago, spent the day crisscrossing the Baltimore and Washington areas.

McGuirk voted early in his south Baltimore district and then spent most of the day there with the voters who elected him to five terms in the legislature. Ocean City Mayor Harry Kelley, another Hughes challenger, stayed in his resort city home after casting his vote.

McGuirk admitted early in the day that he probably needed at least a 40 percent voter turnout to have a chance to upset Hughes but as he circled his district it became obvious that turnout in the city was light as one poll worker after another shook his head and said, "lightest day I've ever seen here, Harry."

Yesterday's gubernatorial results were hardly surprising. Throughout the campaign, discussion had centered not on who would win but on what the margin of victory would be.

The Pascal campaign staff members, frustrated throughout the primary by the lack of interest in their efforts, went into yesterday's primary eagerly anticipating "the main event," as a Pascal spokesman put it. Days before the primary, Pascal scheduled two Thursday press conferences -- in Montgomery County and Baltimore -- to denounce Hughes for too lenient prison policies.

"We're going to take the gloves off," said spokesman Ilene Heaney. "We're not going to be nice about Mr. Hughes' record."

Hughes, too, had already begun plans for the general election. Early this week staff members were emphasizing that their first priority would be to see that the Democrats quickly reunified, emphasizing the importance of McGuirk and his supporters and of Baltimore's popular mayor, William Donald Schaefer, who has been lukewarm in his feelings for the governor.

Both Pascal and Hughes say they would like Schaefer's support, since he commands much loyalty in Baltimore.