Washington — What once looked like a four-lane expressway now looks like a rocky, potholed road ahead for the '84 federal budget. In the House, Democrats this week put together a budget proposal that attempts to turn around two years of effort by President Reagan to shrink the government and boost defense.
Even in the friendlier, Republican-controlled Senate, the way looks rough for the President's proposed spending plans.
When it became clear March 15 that Senate Republicans would not draw up a budget to suit the White House, President Reagan asked for and got, somewhat grudgingly, a three-week delay by the Senate Budget Committee. Senate Budget chairman Pete V. Domenici (R) of New Mexico refused at first, but at last gave in to the President's urgent request for more time to try to win support for his side.
''He is the commander in chief,'' says a Domenici aide, adding that the delay throws the whole budget into uncertainty.
As it now looks, the budget battle will be fought on three fronts.
Newly unified House Democrats have fashioned a ''fairness and growth'' budget that will almost certainly pass next week in the full House. It will be the most liberal House budget by far in the past three years, including about $20 billion in new jobs programs, $1.5 billion added for food stamps and welfare, and $16.7 billion for housing.
Rather than the 10 percent real increase that President Reagan seeks for defense, the House Democratic plan would offer 4 percent.
House Democrats also propose raising 1984 revenues by nearly $30 billion more than the President's budget. And while they don't specify how that money would be raised, the amount is about the same as would be gained by repealing the 10 percent tax cut due next July.
For the first time since President Reagan took office, House Democrats are showing signs of unity on a budget. During the past two years, conservative Democrats often drifted over to the Republican side. But with 26 new Democratic seats, the leadership now has the votes to win.
''I think it's the nearest thing to a consensus that we've ever achieved,'' says House majority leader Jim Wright (D) of Texas. He points out that more than 200 House Democrats participated in the budget deliberations by filling out a questionnaire on their choices for the budget.
Republican House leader Robert H. Michel of Illinois conceded this week that the GOP ''couldn't put through a total substitute,'' and that his only hope is to ''concentrate on several key amendments.''
Even if the Democratic budget does survive intact in the House, it will be modified in conference with the Senate. One Democratic budget aide conceded that he expects some of the domestic dollars to be erased in conference.
Meanwhile, the Democratic House budget becomes a political posture for Democrats who at last have a solid ''Democratic alternative.''
On the second front, the White House now begins a last-ditch effort to win public and Senate support for its defense budget and for saving the tax cuts already in place. Mr. Reagan is expected to modify some of his figures on defense to allow for widespread feelings in both parties that his proposed 10 percent hike is too much.
In his public campaign, Mr. Reagan will no doubt use the Democratic House budget as a foil.
The House budget proposal ''gives the President a good talking point,'' says Sen. Lawton Chiles, ranking Democrat on the Senate Budget Committee. The Florida senator points out that the President can use the House figures to pressure Senate Republicans to compensate by coming closer to his side.
''The President will spend the Easter recess trying to discredit it (the House budget),'' says majority leader Wright. ''That's why he asked them to hold back on the Senate side.''
And on the third front in the Senate, the budget now goes almost back to Square 1, after moving on a fast track for weeks. The committee seemed headed for passing a defense figure at 5 percent growth and adding more domestic spending than the President wants.
But it is far from certain that the next weeks will change many minds on the Senate Budget Committee. ''He's lobbied these guys up here about all he can,'' says the Domenici aide. ''I don't think there's any arm-twisting left.''