Lawmakers get back to business in earnest Monday, trying to wrap up the 101st Congress early enough to campaign in the November elections as the political landscape is being transformed by upheaval in the Middle East.

Awaiting final action is major legislation dealing with the environment, civil rights, child care and campaign finance. Congress also must deal with its most basic task, determining the nation's budget for the coming fiscal year.

How lawmakers handle these issues in the coming weeks, which mark the end of the two-year Congress, will go far in determining how the session is remembered.

The legislators' work is complicated by the crisis in the Persian Gulf, which arose the day before they left for a month-long recess. As the Bush administration started building a U.S. military presence in the gulf region and Saudi Arabia, in a war of nerves with Iraqi President Saddam Hussein, lawmakers have been holding town meetings, eating Rotary Club lunches and touring the world. The gulf turmoil has become entangled in issues ranging from the budget to environmental and energy policy.

Among the high-priority domestic issues is President Bush's nomination of federal appeals court Judge David H. Souter to the Supreme Court. The Senate Judiciary Committee is scheduled to begin hearings Thursday; the Senate is likely to vote on the nomination this fall.

The packed agenda makes it unlikely Congress will meet its adjournment target of Oct. 5 and raises the possibility lawmakers might have to return to Washington for their first post-election session in eight years.

Congressional leaders discourage speculation about a lame-duck session, lest it become a self-fulfilling prophecy. "Everything will be done when everyone believes it's the last week," a House Democratic leadership aide said. "The trick is convincing them it really is the last week."

The impact of the Persian Gulf is felt most directly on the fiscal issues awaiting lawmakers. The cost of the massive U.S. military presence in the region, estimated at $11.3 billion for the coming fiscal year, has made some reluctant to make deep cuts in military spending.

The House is scheduled to begin consideration of the Pentagon budget bill this week. Before Iraq invaded Kuwait on Aug. 2, the Senate and House appeared to be on a collision course in their two versions of the military spending plan for fiscal 1991.

The $289 billion outline approved by the Senate before the August recess would cut Bush's spending request by $18 billion, giving the administration the two additional B-2 radar-evading "stealth" bombers it requested but restructuring the space-based Strategic Defense Initiative (SDI), cutting the military by 100,000 personnel and scaling back plans for mobile ballistic missiles.

The bill awaiting action in the House would cut defense spending by $24 billion, end production of the B-2, slash spending for SDI, shelve both mobile missiles and cut troop strength by 29,500 more than the Senate.

Besides the fiscal issues, the Persian Gulf situation could affect environmental and energy legislation.

Business interests already have begun sniping at clean air legislation, now in a House-Senate conference, arguing this is not the time for costly new regulations. Before the recess, House and Senate negotiators settled one key dispute involving phaseout of chlorofluorocarbons (CFCs) and other ozone-depleting substances.

But most other contentious issues, including controls on air pollutants and acid rain, remain at issue, raising concern among some lawmakers that time may run out unless the conference picks up its pace.

During the August break, Bush signed legislation aimed at preventing oil spills and punishing spillers, but a House-passed bill to create a Department of Environmental Protection has stalled in the Senate.

Lawmakers are faced with a wide range of other issues, including legislation to overturn or modify six recent Supreme Court decisions that limited the impact of federal laws against job discrimination. The House and Senate passed different versions of the bill over protests from the White House that the legislation could lead to racial and other quotas in hiring and promotion of workers.

Although threatening a veto unless the bill is changed to his satisfaction, Bush has said he wants to sign the measure and is expected to push in conference for revisions that Democrats were previously reluctant to make.

Another showdown with the White House is brewing over child care legislation. Differing House and Senate bills to provide federal assistance to families in finding and financing child-care services are before a conference committee. The administration objects to the conference bill's cost and some of its programs, including day care in schools. Bush previously vetoed a bill to give workers unpaid leave to care for newborn children and sick relatives.

Lawmakers are also geared up for their customary election-year drive to appear tough on crime.

The House is scheduled to act soon on its version of crime legislation that was approved by the Senate in July. Both bills would expand the number of federal crimes for which the death penalty can be imposed, although the Senate lists 34 crimes and the House 10.

Unlike the Senate, the House would allow death row inmates to challenge their sentences if they can prove that race was a factor in sentencing. The Senate bill includes a limited ban on semiautomatic assault weapons. Separate committee-approved bills are pending in the House to curb assault weapons and impose a seven-day waiting period for the purchase of handguns.

Anxious to take a tough stand before facing angry voters over the August recess, the House and Senate whipped through legislation beefing up savings and loan enforcement efforts and imposing stiff new penalties for bank and thrift industry fraud. When the lawmakers come back, they will deal with regulators' needs for tens of billions of dollars more to keep the S&L bailout operation from running out of money by the end of the year.

Also pending are some matters directly affecting lawmakers: campaign finance and questions of congressional ethics and pay.

The House and Senate passed significantly different bills to overhaul laws governing financing of congressional campaigns. Both versions would create voluntary spending limits with incentives for candidates to comply. But the House bill tilts more toward incumbents and would continue to allow scaled-back contributions from political action committees. The Senate would outlaw such contributions. Bush has said he will veto any bill with spending limits, and a difficult conference is expected.

The Senate version of campaign finance legislation includes a ban on honoraria for senators, scheduled to take effect when an already approved ban on speaking fees for House members starts Jan. 1.

The Senate also faces the prospect of preliminary action by its ethics committee in the case of the "Keating Five" senators who have been accused of intervening with federal regulators on behalf of savings and loan executive Charles H. Keating Jr., who contributed to their campaigns and favored causes.

Also awaiting final action is a five-year farm bill. The House and Senate passed differing versions, setting the stage for a major struggle with the administration, which insists that both bills are too costly.