When Maryland's newly elected legislature convenes Wednesday in Annapolis, lawmakers will usher in the end of an era: the final term of Gov. William Donald Schaefer, last of a generation of politicians who symbolized and sustained Baltimore's political dominance.

With no obvious successor from the city, Schaefer, 69, could witness the final emergence of Washington suburban power that has been growing steadily since the 1950s but has exerted itself so far only sporadically.

Over the next few years, Baltimore is likely to lose seats in the General Assembly and perhaps see the governor's mansion occupied by a politician closer to Maryland's "other" metropolis. In the meantime, officials are trying to divine what that means for Baltimore, and whether Montgomery, Prince George's and other counties in Washington's shadow can capitalize on their growing demographic and economic strength.

The answers are unlikely to come quickly. Schaefer (D) takes the oath of office next week and promises to dominate events of his second term as fully as in his first. But the issue of shifting power is relevant now: With the state's economy sliding, Baltimore and other poorer jurisdictions are more desperate for help while suburban Washington taxpayers and politicians are girding for a fight against proposed tax increases and plans to redistribute the wealth.

"There has always been . . . 'suburban areas versus the city area,' and the city has dominated," said Prince George's County Executive Parris N. Glendening, a possible Democratic gubernatorial candidate in 1994. "You are seeing a lot of changes in those patterns . . . . That does not mean the suburban area will dominate . . . . But the long-term dynamics have changed . . . in terms of competing on an equal footing."

No one expects the city to fall into total eclipse. Baltimore remains the state's financial, cultural and civic center, and that will carry political weight regardless of the city's numbers and representation. In addition, the suburban counties are a disparate lot. Neighboring Prince George's and Montgomery don't always cooperate, and have fared differently in Annapolis: Prince George's is a recognized power, while Montgomery has struggled for influence.

But it also is clear that the clout that enabled Baltimore to produce a nearly unbroken string of governors, from Albert C. Ritchie in 1920 to Schaefer in 1986, is waning. When Schaefer was reelected in November, his margin of victory came from Montgomery and Prince George's counties.

"The traditional coalitions which centered on Baltimore city are unraveling," said former state senator John Bambacus, a Republican from Western Maryland. "The question is how well the Washington suburbs can coalesce."

The trend has been building since Baltimore's population began falling in the 1950s, and last year reached a symbolic plateau. In August, U.S. Census Bureau figures showed that Montgomery County, after a decade of rapid growth, had become the state's most populous jurisdiction with an estimated 733,000 residents, and remained its wealthiest. While Montgomery was attracting new residents at a rate of 17,000 a year, Baltimore saw its population slip from 786,000 to 720,000. Close behind is Prince George's, with 719,000 residents.

In addition, Glendening and others noted, the November elections marked the first time that the two Washington suburban counties produced more votes than Baltimore and Baltimore County, a sign of shifting political strength.

Further fueling the political shift, legislative districts will be redrawn for the 1994 elections, and Baltimore is likely to lose as many as eight of its 36 legislators, while Montgomery and Prince George's may gain an equal number.

Anticipating that political drain, and with the city's courts, schools and government strapped for cash, Baltimore Mayor Kurt L. Schmoke said he hopes the legislature will approve a significant Baltimore aid package soon, before those changes take full effect.

The city fared particularly well during Schaefer's first term: Aid to Baltimore increased from $440 million to $623 million, and the governor pushed through a commuter rail line and new baseball stadium for the Baltimore area. This year, Schmoke and other city politicians are hoping for a state-backed expansion of the Baltimore Convention Center, a state takeover of the court system and an $800 million statewide tax increase and redistribution package that will benefit the city.

"My sense is that the Washington suburban counties are going to play their strongest role in statewide politics that they have played in any time," Schmoke said. "We need to move quickly and try to get a fair hearing."

The shift in political influence will depend in part on how well politicians from the Washington suburbs can exploit their electoral strength. University of Maryland historian George Callcott said political power has rested outside Baltimore since the 1960s, but the young, "atomized" suburbs have not been good at wielding it. While Baltimore's true machine heyday is long past -- the city controlled the governor's mansion for all but four years from 1920 to 1960 -- recent decades have been a transitional period that kept the city's dominance alive, he said.

Three governors have been elected from outside Baltimore since the 1950s, but two have had strong connections to the city: Spiro T. Agnew was born in Baltimore and was Baltimore County executive when he was elected in 1966, and Harry Hughes, elected in 1978 and 1982, was an Eastern Shore native whose professional and political career was rooted in Baltimore.

In the immediate future, most officials doubt the emergence of a "suburban axis" that would rival the power Baltimore wielded earlier in the century, when it had as much as half the state's population. There is no cohesive organization or issue that is likely to unite voters in counties that are increasingly diverse ethnically, economically and even geographically.

There are common concerns, such as growth, education and the environment, state Senate President Thomas V. Mike Miller Jr. (D-Prince George's) said, but "nobody can deliver votes any more. The trend is toward fewer and fewer coalitions . . . . I see the Washington area as having a unique set of problems and needs, but I honestly don't see a major political alliance."