House Democratic leaders seized the initiative on jobs as the lame-duck session of Congress opened yesterday. They vowed to push for quick approval of an expanded job-creating program, including $5 billion for public works repairs and legislation to aid the housing industry.

As outlined by House Speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.), the new proposals will be in addition to a bipartisan $5.5 billion plan to finance highway, bridge and transit repairs through a 5-cent-a-gallon increase in the federal gasoline tax.

The highway plan would create an estimated 320,000 jobs. Democrats said their additional plan probably would create another 250,000 to 300,000 jobs to help combat the country's soaring unemployment rate, now 10.4 percent.

The gas tax and highway measure, backed by President Reagan as well as leaders of both parties in the House and Senate, was introduced yesterday in the Senate and swift approval is expected.

But President Reagan has indicated he may resist further anti-recession legislation, and prospects for passage of the additional Democratic bills in the lame-duck session were not so bright.

Senate Majority Leader Howard H. Baker Jr. (R-Tenn.) said he doubted they would be approved by the Senate in the three-week post-election session, although Senate Minority Leader Robert C. Byrd (D-W.Va.) said he and other Senate Democrats will be pushing for some kind of an expanded jobs program.

Conceding that pre-Christmas passage of the entire Democratic plan may be difficult, House Democratic aides said they thought at least some pieces of it may be enacted this year.

"Our first priority in the current session is to create jobs," O'Neill told reporters in a briefing before the lame-duck session opened.

"The highway bill is a start. I am hopeful that we will win bipartisan support for a broader job-creating package and take action on this package before Christmas."

Unlike the highway measure, the Democratic proposal would not be financed by a tax increase. O'Neill conceded it would increase the deficit but said, "What's more important -- the deficit that's out there or people starving and without a roof over their heads."

O'Neill said he and other House Democrats are drafting legislation to provide about $5 billion for such projects as repair of government office buildings, veterans' hospitals and public housing projects.

In addition, the House Democrats plan to move ahead with a housing reauthorization bill of roughly $10 billion that could include a mortgage subsidy for prospective home buyers, although aides said the subsidy provisions may not be pushed in light of opposition from the home-building industry.

President Reagan earlier in the year vetoed a bill that contained mortgage subsidy provisions, which had industry support at the time. Democrats on the House Banking Committee are scheduled to meet tomorrow to decide what will be in the housing authorization measure.

Details of the public works jobs bill have not been nailed down either. But aides said the general purpose will be "quick generation of jobs that result in something to show for the effort." The emphasis is likely to be on repair work that has already been planned, rather than on construction of new facilities, the aides said.

Asked about the Democratic plans, Baker appeared to rule out Senate action this year on anything but the highways measure, saying, "I don't think that we're going to have time in three weeks . . . to do much more than that."

"I don't think that's enough," responded Byrd. Byrd suggested a program of low-interest loans to help modernization efforts by steel and other industries and said Senate Democrats will meet today to map out their plans for the session.

Also to be unveiled today is a jobs-related program from President Reagan that is expected to include formal endorsement of the highway measure and a renewal of support for prompt action on his proposal for "enterprise zones" to spur rehabilition of run-down neighborhoods through tax and other incentives.

As of late yesterday, congressional leaders said they did not know whether the president would also propose advancing next year's scheduled income tax cut from July to January, a proposal that has drawn little support from Republican leaders in Congress. Congressional sources said variations on the theme of tax-cut acceleration still were under consideration at the White House yesterday.

If the program is too ambitious, "I can't conceive of it getting the time of day in the lame-duck," said House Minority Leader Robert H. Michel (R-Ill.)

Among the other issues that will come up in the lame-duck session, in addition to appropriations bills, is the MX missile, and O'Neill said it is "in serious trouble" in the House.

Kenneth Duberstein, chief lobbyist for the White House, told reporters at a luncheon that Reagan has made at least a dozen phone calls to lawmakers to help drum up support for the MX and its controversial "Dense Pack" deployment system.

But he said the vote on efforts to deny funding for production of the missile, which is expected in connection with the defense appropriations bill or related funding measures, looks "exceedingly close." Another vote that is expected next year on scuttling the deployment system also appears "very, very tough," Duberstein said.