A poll conducted this month by Gov. Harry Hughes' reelection campaign shows him leading his most likely Republican challenger by a 3-to-1 margin, with more than 60 percent of the voters rating his job performance as above average or excellent, the governor's pollster said in an interview today.

Sixty-four percent of the 600 voters polled said they would be "inclined" to vote for Hughes today, regardless of who opposes him, and more than three-fourths said state government and the quality of life in Maryland have improved or stayed the same since he took office, the pollster said.

The poll by Consensus Inc. of New York, conducted between Jan. 5 and 10, sampled registered voters who mirror those most likely to turn out for the November election, according to Tully Plesser, president of the polling firm, which is among the largest in the country.

The poll shows the 55-year-old Hughes faring considerably better than he had in surveys released last fall, which had indicated an erosion in his popularity and a revealed a public perception of him as a weak governor.

Plesser, who disclosed portions of the poll in an interview with The Washington Post, declined to detail any weaknesses in the Democratic governor's candidacy, and said the results indicate a "very strong incumbency."

Among the factors strongly in Hughes' favor, Plesser said, were the strong Democratic tendencies of the voters polled. Although they gave President Reagan a 56 percent positive job performance rating, Hughes' rating on the same question was 65 percent, according to Plesser. And 44 percent gave the president negative ratings, compared to 35 percent for Hughes, he said.

As in other polls, Hughes was strongest in the Washington suburbs, where the governor received a 76.3 percent positive rating. In a head-to-head match with his most likely Republican challenger, Anne Arundel County Executive Robert A. Pascal, Hughes received the support of 70 percent of the sample, to Pascal's 20 percent, with 10 percent undecided. The governor led Pascal in every county, including the Republican's home base of Anne Arundel, according to Plesser.

Hughes, who won a surprise victory in 1978 as a political outsider running on an integrity-in-government platform, said in an interview tonight that he considered the poll results "very reassuring," and a rebuttal to criticism from some veteran Maryland politicians who have criticized his low-key style of leadership in Annapolis.

"I don't ignore the politicians, but I think this does reinforce what I've felt all along, that the people aren't sharing the views of some of the politicians. And I think some politicians don't share those views," the governor said. Hughes first received the results over the weekend in a five-hour briefing with Plesser, several members of his gubernatorial staff and his campaign director, Joseph Coale.

In addition to the head-to-head match with Pascal, the poll tested Hughes' popularity with two potential running mates, House Speaker Benjamin L. Cardin of Baltimore and Baltimore County Executive Donald Hutchinson, Plesser said. But the results were inconclusive, since neither man was well known enough to make a clear difference in the governor's strength, Coale explained.

Hughes is expected to drop Lt. Gov. Samuel Bogley from his November ticket, but has not yet decided on a running mate, although Hutchinson is said to be his first choice. Both Hutchinson and Cardin say they now plan to seek reelection rather than join Hughes' ticket, but neither has ruled it out.

"I'm not seeking the position, but I'm not ruling out options," said Cardin, who added that he did not know Hughes had included him in the poll.

The $16,000 poll was the first of several that Consensus Inc. is expected to conduct for Hughes between now and the election. Plesser said the numbers could change in the next months, since more than 70 percent of those polled said they did not recognize Pascal's name, or didn't know enough about him to evaluate him. By contrast, 91 percent said they knew enough about Hughes to rate his performance, according to Plesser, and less than 1 percent said they had never heard of him. If Pascal, who has not yet officially declared his candidacy, can increase his name recognition through media campaigns, his ratings could rise, Plesser said.

Plesser, who has conducted polls for several governors and senators, said Hughes appears to be in "as good a starting point for an incumbent as you're going to find." He said it is unusual for an incumbent to receive higher than 60 percent favorable ratings both in general voter perceptions and for his job performance.

"We're not saying this is how it's going to look at the end of the contest, but this shows an electorate that likes Democrats, that expects Democrats to win, that thinks favorably of its Democratic governor, that doesn't think as favorably of a Republican president. It's certainly a favorable starting point and really poses some serious problems for anyone who would challenge that."