IN PRINCE GEORGE'S COUNTY, where the Democrats have controlled the county council and a Republican has been in charge of the executive branch, Tuesday's elections will set the stage for any reversals or reaffirmations of this two-party arrangement on Nov. 2. No one in either branch would pretend that relations between the council and the county executive over the last four years have been as good as they could or should be, but neither can it be said that good government has suffered unduly in Prince George's -- from many conflicts accommodation did come. Besides, Lawrence Hogan, who has seemed to revel in this atmosphere, is leaving in pursuit of statewide office.

To assess the qualifications of candidates seeking to be their party's choice for either county executive or a seat on the council, a voter might look to their views on TRIM, which is the financial constraint now affecting almost every aspect of county government. Any office-seeker insisting that TRIM is inviolate, or that no adjustment to your financial set is necessary, is not likely to have helpful responses to any other important concerns voters may raise in the next four years. Whatever healthy fiscal influence TRIM may have had in the past -- and even many of its initial opponents will acknowledge that the tightening effect was not all bad -- time and inflation have a way of spoiling the fruits of fru- gality.

Voters in each party are fortunate that there are candidates running who recognize that TRIM must be modified in some way if Prince George's is to address or compensate for decreases in state and federal largess. And that is only to keep even, and forget any new or expanded programs. Plus 4, which will be on the ballot in November, would modify TRIM by allowing the county council to increase by up to 4 percent annually the amount of property tax revenues collected. That's the least candidates should support -- and even if it is approved, the application of it and the modest amount of money it would yield will still be up to the council.

In the race for one school board seat there are more localized concerns that will affect a voter's judgments. Still, the responses of candidates to questions of financial priority are important in an atmosphere where requests for money to combat crime have tended recently to upstage those for public education. Obviously some reasonable compromise should be struck and the thoughtfulness of each candidate on this question should weigh heavily in reaching a decision.