Political power in Maryland will shift dramatically as a result of the 1980 census, with the City of Baltimore losing influence in the state legislature and Congress, and the outer Washington suburbs of Anne Arundel and Howard counties gaining strength.

Baltimore's powerful legislative delegation, which has faced growing opposition from suburban legislators in recent sessions of the General Assembly, could lose eight seats in the two chambers and slip to its smallest size since the one-man, one-vote reapportionment of the mid-1960s.

And while Baltimore will retain its two congressional seats, the city's political strength will be diluted as districts are redrawn to include larger portions of the surrounding suburbs to make up for the city's estimated 13.5 percent population loss in the last decade.

The Washington suburbs are expected to lose only slightly as a result of the census. Prince George's County will probably have to share one state senator with neighboring Charles County since its population did not keep pace with the state's, but Montgomery County is expected to retain its present legislative strength.

These outlines of Maryland's new political map began to emerge this week after the U.S. Supreme Court allowed the 1980 census to be released to President Carter, despite pending challenges by Baltimore and other cities whose leaders contend their populations were undercounted.

Maryland officials say they took the high court's action as a signal that the challenges by Baltimore and several cities will not be successful, clearing the way for the state to start bringing its legislative boundaries into line with the new population figures.

Although the General Assembly will not vote on reapportionment until the 1982 session, politicians around the state are already sizing up how changes in legislative and congressional district lines could shape dozens of political careers and affect the power held by Maryland's various regions.

"People warned me when I ran for the legislature that something awful was going to happen at the end of my first term. They said it was called reapportionment," said Del. Timothy Maloney (D-Prince George's). "They said people who had been my friends for years would stop talking to me, and people who never spoke to me before would suddenly be my friends. They were exactly right."

So far, the hottest speculation centers on how the city of Baltimore and population equivalent to six state delegates and two state senators. Some officials in neighboring Anne Arundel and Baltimore counties are known to be worried that portions of their populations will be lumped into the shrunken Baltimore districts, leaving the city still in control of those districts despite the shift in population to the suburbs.

Baltimore's legislative leaders, traditionally adept in the wielding of power, profess that they are not concerned that the impending changes will diminish the city's legendary clout in the legislature, even though the number of delegates from the city could shrink to 27 after the 1982 reapportionment, compared to 33 now, and 43 in 1967. They point out that Baltimore will still have the state's largest single delegation, with 33 of the 188 representatives in the two chambers.

"I'm not so sure that it's your own numbers that matter, so much as what you do with what you have," said Del. Paul Weisengoff (D-Baltimore), a 13-year veteran of the House of Delegates with much experience in legislative horsetrading.

Still, when it comes time to devise state aid formulas or discuss additional funding for the subway system now under construction the city will be in its weakest position since the 1960s, when a series of court decisions led to reapportioning legislative districts on the basis of population and greatly enhanced the power of urban areas.

The expected changes in the congressional district map have also stirred concerns in the city, since Rep. Barbara Mikulski and Rep. Parren Mitchell, both from the inner city, have lost more than 10 percent of their districts. As a result, their present districts will have to be redrawn to include more of the surrounding suburbs.

This is not expected to pose problems for Mikulski, whose district already includes areas of Anne Arundel and Baltimore counties, but supporters of Mitchell, the state's only black congressman, have expressed concern about the dilution of his power base if his district expands into Baltimore County.

The most logical expansion of Mitchell's district would give rise to another struggle. It would take in northwest Baltimore, a heavily Jewish area that fought during the last reapportionment to be included in the adjoining congressional district, where much of the Baltimore area's Jewish population now lives.

The other major changes in the congressional map will reshape the sprawling 1st District, which now stretches from Southern Maryland along the Eastern Shore up to the Delaware line, and the 6th District, represented by Beverly Byron, which until now has included both Western Maryland and the city of Columbia.

Legislators had planned to redraw the 1st District by eliminating Southern Maryland and merging it into the Prince George's County district now represented by Gladys Spellman. But that idea may be scuttled now that Roy Dyson, a Southern Marylander and Democrat elected in November, holds that congressional seat and the state's leading Democrats do not want to lose it.

The growth of the City of Columbia means Byron's district is now too large, so there is speculation that Columbia will be shifted into a hybrid of Rep. Marjorie Holt's district, which now includes portions of Anne Arundel and Prince George's counties.

Gov. Harry Hughes is expected to submit his reapportionment plan at the end of this year, and the legislature will debate and vote on it in the 1982 session. The new district lines will not take effect until the 1984 elections, although they could be delayed beyond then, if the reapportionment plan is overturned by court challenges, as were the last two plans approved by the General Assembly.