House Budget Committee Chairman James R. Jones (D-Okla.) declared yesterday that Congress has reached a budget "stalemate" and threatened to force the issue by simply tossing President Reagan's budget out on the House floor.

As Jones was intensifying pressure on Reagan to signal a willingness to compromise and thereby avoid the embarrassment of an almost certain budget defeat, Republicans shifted the focus of their search for budget alternatives from the Republican-controlled Senate to the Democratic House.

In doing so, they were seeking partly to force Democratic leaders to take more responsibility in the politically difficult task of cutting spending and raising taxes billions of dollars to reduce Reagan's huge projected deficits.

The Republicans' shift in strategy, announced by House Minority Leader Robert H. Michel (R-Ill.) after an hour-long meeting of top Senate and House Republican leaders, came as a surprise.

House GOP sources said it reflected a sense that House Republicans may be closer to a consensus than their Senate counterparts, along with a desire to see whether the House Democratic leadership is really interested in compromise.

"I think we have a real responsibility here to come up . . . with a bipartisan agreement," said Michel, who said he was already talking with Jones and was willing to do so with Speaker Thomas P. O'Neill Jr. (D-Mass.) and other Democratic leaders as well.

The problem is that the Democrats, wary of being mousetrapped by Reagan into proposing controversial tax increases and spending cuts during an election year, are insisting on a signal from Reagan that he's willing to give on such sensitive issues as defense spending, taxes and cuts in major benefit programs like Social Security. So far Reagan has talked only generally of compromise and refused to budge on the big items, characterizing his budget critics as high-tax advocates.

O'Neill is regarded by many Republicans as critical to the success of any bipartisan compromise in Congress, and he shied away yesterday from Jones' idea of reporting Reagan's budget to the House floor, saying it might accomplish nothing more than "embarrassing the president."

But O'Neill and other Democrats indicated that Jones' suggestion was well received at a House Democratic caucus yesterday morning. "There was a warmth for it," O'Neill told reporters after the caucus. O'Neill said he liked the idea at first but had misgivings as he thought more about it and planned to talk with Jones about whether such a strategy should be pursued.

In conversations with reporters, Jones emphasized that he still wants a bipartisan budget but added, "We can't get there unless there is a willingness to compromise," by the president as well as congressional Republicans.

"What we're hearing so far does not sound like a desire for bipartisan cooperation," said Jones. "If that is the case, then we may have no alternative but to ask the president's budget to be reported to the floor to see how much support there is for it." Even Republicans concede it would probably not get many votes.

Describing a House vote on Reagan's budget as a "genuine option," Jones said that "right now we are at a stalemate and we have to break the logjam . . . . I'm not being cutesy here, I'm trying to break the logjam." The only way to do so, he added, may be to "fully explore the president's budget" on the House floor.

Once on the floor, it could be called up by Jones within 10 days. Conceivably it could be subjected to unlimited amendments as well as an up-or-down vote.

Jones also expressed doubts whether bilateral talks between House Democrats and Republicans could produce a bipartisan budget compromise without Reagan's cooperation, a point O'Neill has also underscored repeatedly. "Michel can't negotiate independently unless he gets a signal from the White House," said Jones.

Meanwhile, White House communications director David R. Gergen criticized a proposal from Senate Democrats on Tuesday that Reagan rewrite his budget to take into account pressures for deferral of the 1983 tax cut and future indexing of taxes to inflation and for a reduction in defense spending. "We believe it is badly flawed," said Gergen, contending that most Americans want lower taxes and a stronger defense.