Last Sunday the three Democratic candidates for the Maryland House of Delegates in the New Carrollton-based 23rd Distric got together for a strategy session with a few of the district's more active party workers.

Before long, one seasoned campaigner couldn't resist observing that their work was somewhat unimportant. If all the Democratic candidates were to leave the country until the general election, he said, their Republican opponents would probably still have little chance of winning.

Incumbent Del. Frank Pesci was outraged.

"Don't tell me I don't have to campaign," he fumed later. "I turned down an invitation to work in an emerging African nation this month so I could be here. I don't want to think I don't have a race."

Pesci, who concedes his campaign has not reached any level of intensity" since the Democratic primary last month, was joking, of course. Along with fellow delegate candidates Robert Redding and David Bird and incumbant Sen. Thomas P. O'Reilly, Pesci does not expect serious opposition from the 23rd District's Republicans.

In fact, the Democrates are already confidently enlisting in the tougher races of gubernatorial hopeful Harry Hughes and Prince George's County Executive Winfield Kelly, so little do they fear the Republicans, who are outnumbered 3-1 by Democrats in the District.

Republican House of Delegate candidates Ana Bartash and Joe Provencal and Senate contender Richard Blancato do not think the race will be one-sided, however. "I think I'm going to surprise a lot of the experts," says Blancato.

Blancato, who quit his job as a U.S. marshal last June to work full-time on his campaign, says he will knock on the door of every registered voter in the district twice by the election, and hopes hard work, combined with criticism of O'Reilly's record, will earn him an upset in the senate race.

But like Bartash, a New Carrollton homemaker, and Provencal, a retired prison system employe active in veterans' organizations. Blancato suffers from a lack of campaign funds, organization and major campaign issues essential in a race against candidates like Pesci and Redding, who are well-known from their eight years of experience in the legislature.

Redding, Pesci and Bird have much the same background in politics and share some of the same philosophical roots. Each supports such progressive measures as a graduated state income tax and a localized district election for the Prince George's County Council. And each is, in Bird's words, "a child of William Goodman," a longtime Democratic independent who lost to O'Reilly in the Democratic senate primary.

Both Redding and Pesci worked for Goodman when he was a delegate in Annapolis during the 1960s, and Bird and Goodman this year co-sponsored the Tax Reform Initiative by Marylanders (TRIM) ballot referendum in the county, which would freeze property tax collections during coming years at the 1979 level - about $140 million.

Bird is focusing his campaign on the TRIM referendum, and, with the endorsements of Kelly and most of the other Democrats in the county, expects that the ballot amendment will pass. Kelly has said that the county "could live with" TRIM for two years without major cost in services.

Meanwhile, Pesci is working on raising interest in a ballot amendment he sponsored that would localize the election of five of the 11 County Council members to specific districts.

O'Reilly has been responding to the aggressive campaign of Blancato by emphasizing his work on spending issues during his four years in the senate. He says that if he is reelected this year, he will work for passage of a bill that would require state budgets that rise more than the precentage of increase in the consumer price index to be approved by a large majority of the legislature.

Provencal, as a former prison official, stresses law-and-order issues and favors more mandatory penalties and less leniency in probation for convicted felons.

Blancato, like all the candidates in the race, stresses property tax reform, but also favors a return to the basics in education and a new emphasis on innovative pre-school teaching for children.