A proposed 1-cent sales tax increase to pay for Metro operating deficits and highway improvements in Northern Virginia died in the Virginia House of Delegates yesterday when it fell a single vote short of a required majority of 51.

The House voted 50 to 48 in favor of authority for five cities and counties in the Washington suburbs to raise the sales tax from 4 cents to 5 cents on the dollar, but all tax measures require an affirmative vote by more than half of the 100 House members.

A frantic effort by Northern Virginians to engineer reconsideration of the measure and switch a negative vote was cut off by adjournment of the House for the day.

Chances for future reconsideration are foreclosed by assembly procedures. Since the bill originated in the Senate, where it was approved by a wide margin, the defeat of it must now be communicated to the Senate, putting it our of reach of House reconsideration.

House Speaker John Warren Cooke (D-Mathews) said in answer to questions that the negative vote would be communicated "in the normal course" to the Senate before today's session. Cooke was among the 48 who voted against the bill.

The end of the sales tax controversy in the House came as the Senate ended another dispute that has occupied the General Assembly for years by approving party labels of candidates on ballots in statewide elections.

The overwhelmingly Democratic Senate voted 27 to 10 to approve a House bill that will permit party designation in this year's Senate election.

In view of strong opposition in the House to local sales taxes, a levy traditionally considered to be a source of statewide revenue, the narrow margin surprised many."I'm amazed we came this close," Metro general manager Theodore Lutz said in an interview.

Lutz was one member of a large group of Metro and Northern Virginia local government officials who were in the Capitol today for the unhappy climax of their intensive lobbying effort for the sales tax authority.

Del. Warren G. Stambuagh (D-Arlington), who managed the bill on the House floor, pleaded with the delegates to let the Northern Virginians use the sales tax to ease the burden that Metro deficits are placing on homeowners who must pay increasing real estate tax bills, especially in Arlington and Alexandria.

Despite Stambaugh's arguments, the proposal got only gruding support from some Fairfax County delegates who noted that Fairfax residents would pay for more money in sales taxes than they would get back in credits against their share of Metro operating deficits.

Even after an amendment was added that would have permitted Fairfax to veto the tax through a refer- endum in the November election, two Republican delegates from the county, Robert E. Harris and Robert L. Thoburn, voted against the bill.

A third Fairfax Republican, Martin H. Perper, a supporter of the bill, is hospitalized in Washington with chest pains and was not present for the vote. His yes vote would have carried the bill, assuming all other votes remained unchanged.

However, by the time the bill was amended to its final form, some of its supporters feared it would never have resulted in a sales tax for Metro.

"With the referendum amendment on it, I'm afraid it wasn't worth much to us," Sen. Wiley F. Mitchell (R-Alexandria) said in an interview. Alexandria City Council member Robert Calhoun expressed the same view.

The referendum amendment was offered by Del. Warren E. Barry (R-Fairfax) and passed, 80 to 3. Barry contended in debate that Fairfax resdents would pay an estimate $20.3 million in new sales taxes in the next fiscal year but receive a guaranteed reduction in other taxes of only $9.8 million, an amount equal to the county share of the rising Metro deficit.

"I feel the people of Fairfax ought to be able to vote on this tax with full knowledge of the impact on them" he said.

The feature of the bill requiring a reduction in property and other taxes to offset the sales tax increase was added in the House Finance Committee. The tax reduction would have been equal to each city's and county's contribution toward paying the Metro deficit, Barry explained.

In Arlington and Alexandria, the share of the Metro dificit exceeds the estimated sales tax collection. However, in Fairfax County, Falls Church and Fairfax City, the sales tax would have exceeded Metro payments.

Northern Virginians already pay the heaviest sales tax in the Washington area, although the Maryland and District of Columbia rates of 5 cents on the dollar are a penny higher. The Virginia tax applies to more purchases, notably food, making the tax paid by individuals and families of equal income higher in Virginia.

Influential House members, including Majority Leader A. L. Philpott (D-Henry), opposed the bill becasue they feared its passage would make it difficult to meet future statewide revenue needs with a sales tax increase.

The Northern Virginians agreed to a committee amendment that would have repealed their local tax automatically if the assembly approved a statewide increase in the sale levy.

However, opponents suggested in debate that the large bloc of Northern Virginia House votes - 16 in the cities and counties served by Metro - would never support a statewide increase that would result in repeal of their transportation tax.

In the Senate vote on party designation of candidates on state election ballots 27 Democrats voted in favor of the measure while five Democrats and all five Republicans in the Senate voted against it.

Party labeling on ballots has been a top legislative goal of the sate Democratic party organization for years.

However, despite lopsided Democratic majorities in both houses of the assembly, the measure has been regularly defeated in the past.

The most influential opponents of party designation in the past had been conservative Democrats who depend upon Republicans votes to win state races. Virginia has been voting heavily for Republican candidates in presidential, U.S. Senate and gubernatorial contests during the last 10 years.