Maryland Gov. Harry Hughes' proposal for a new gasoline tax already has run into a thicket of political obstacles, notably the reluctance of many legislators to vote for a tax increase in an election year.

The governor's transportation package for the 1982 General Assembly session aims to shore up the state's financially strapped road and bridge program with a 4 percent tax on the wholesale price of gasoline. Officials expect the tax to be passed on to consumers, which could raise the present price of gasoline by 4.4 cents a gallon, according to new Transportation Secretary Lowell K. Bridwell, who unveiled the package this week.

Maryland motorists now pay a flat 9-cents-per-gallon tax on gasoline at the pump.

"The problem is, it's an election year," said Del. Gerard Devlin (D-Prince George's), vice chairman of the House Ways and Means Committee, which will rule on the fate of the proposal before it reaches the House floor. "And it's very hard to get a tax increase in an election year."

Devlin and other legislative leaders say they agree with Hughes that the state badly needs more money for roads and bridges, many of which are dangerously dilapidated, but they are unsure that his package provides the answers. Nonetheless, House Speaker Benjamin L. Cardin (D-Baltimore) said he is hopeful that a consensus will emerge, particularly since Hughes presented the package well in advance of the legislative session, which convenes Jan. 13.

For now, the proposal appears to have reinforced the traditional rural-urban split in the General Assembly, with both camps expressing dis-satisfaction over how Hughes proposes to distribute the $635 million that his program would raise. Almost three-fourths of the money will go to the state, and the rest to local governments, with the city of Baltimore getting the biggest chunk -- a formula that has angered rural and some suburban lawmakers.

In addition, both the rural and urban factions say they are unhappy that the package does not address the financial problems posed by the increasingly costly mass transit systems in the Baltimore and Washington areas. Partly for that reason, many legislators say the proposal amounts to "a big Band-Aid," as Sen. John Cade (R-Anne Arundel) put it.

Members of a joint House-Senate committee that has been studying the DOT's problems said that they may attempt to cut the tax in half. Others say they want to cap the tax, in case gas prices skyrocket.

But Sen. Laurence Levitan (D-Montgomery), who chairs the committee that is handling the proposal in the Senate, said that urban legislators may have no choice but to support the program, even if they remain displeased with the focus on roads over mass transit.

"If we don't help solve the road problems for the rural areas and some of our own counties, the legislature may come back in a few years and take away substantial amounts of the money the state is putting into Metro now," said Levitan, whose county executive has called for a gas tax to pay for badly needed road improvements.

The Hughes package also proposes an increase in the registration fees for heavy trucks that would bring in $15 million a year to pay for damage they do to state roads.

The package represents an attempt to resolve a looming financial crisis in the state's transportation trust fund, which pays for bridges and highways, mass transit, and the port and rail programs. There is speculation the fund could face bankruptcy by 1986, since the present tax has been bringing in less money as motorists use less gas.

A smaller gas tax proposal foundered in the 1981 General Assembly session, with legislators laying much of the blame on Hughes, who did not announce his support of the package until late in the session. Many of those legislators praised Hughes yesterday for unveiling his 1982 package so early, although some noted that the move has given his opponents extra time to coalesce and has given both sides extra time to worry about the consequences of voting for a tax increase.

"The governor is showing leadership in coming out on this," said Del. Tommie Broadwater (D-Prince George's). "But on this particular issue, in an election year, I don't know if I'd want to be leading."