After four months of shadowboxing among Republicans over details of a deficit-reduction plan, Senate Majority Leader Robert J. Dole (R-Kan.) was asked recently if the goal still was a cut of $52 billion next year.

What really would please him, Dole said with a wry smile, is 52 votes.

Dole's comment, made partly in jest, illustrates his dilemma as the Senate moves slowly through tortuous parliamentary procedures to a series of showdown votes on deficit reductions, starting today with two Democratic alternatives.

With his reputation as the new leader of the Senate hanging in the balance, Dole still is pushing relentlessly to assemble a plan to cut deficits of more than $200 billion by half over the next three years. But, although support for his goal is wide and deep, Dole has yet to find a consensus on how to get there as he probes for common ground between conflicting demands of President Reagan and Senate Republicans, especially the 22 whose seats will be contested next year.

So the great crusade for a cause has turned into trench warfare for votes, with the final shape of the plan more likely to reflect the needs of North Dakota farmers or Florida retirees than a coherent strategy for fiscal reform.

By agreeing to a fifth year of drastic retrenchment in domestic spending, coupled with big defense spending increases and no increase in taxes, Dole won over Reagan, only to set off a rebellion within his own ranks in the Senate.

Farm Belt senators demanded that cutbacks in rural programs be modified; Florida and New York senators rebelled at proposed limits on Social Security benefit increases; senators along popular Amtrak routes banded together to save the rail system from termination. Some liberals demanded tax increases that, if included, would cause a revolt among conservatives.

The White House tried to cut through these parochial concerns by building pressure for the package as a whole, including a nationally televised speech by Reagan on its behalf, but they have had little discernible impact.

Senators complained privately that the speech fell flat and that the theme was beginning to "sound like a broken record," as one Republican put it. And there was little, if any, follow-through. Despite promises of presidential telephone calls from the Bonn summit, no senators could be found who had received one.

By improvisation, ego-massaging, vote trading and a little sleight-of-hand, Dole narrowly got his compromise with the White House over its first procedural hurdle, winning by 50 to 49 after guaranteeing senators a chance to pick it to pieces later if they wanted to.

But when specific issues came to a vote, the package ran into a shredding operation. Defense spending increases were whittled back more than Reagan wanted, while a limitation on inflation adjustments for Social Security that had won his grudging approval was dropped. Some funds for Medicare and Medicaid had to be restored to prevent even bigger losses.

But these were preliminary votes, offering senators a chance to look good on a particular issue before confronting the real choices in a comprehensive compromise. Or so Dole hopes as he tries to put together a final agreement that, for instance, probably will include some modification of Social Security adjustments.

With the administration reportedly uneasy over the Senate's actions, Office of Management and Budget Director David A. Stockman has asked Dole to hold off final action until Reagan returns Friday, presumably so he can have an impact on any further deal-making.

Dole has said any final agreement "will be with White House approval." But he also has said that, because of likely GOP defections, he needs some Democratic votes to prevail. Republicans control the Senate, 53 to 47, but Sen. John C. East (R-N.C.) is hospitalized. Vice President Bush is an extra Republican vote but only in case of a tie.

This gives the Senate Democrats powerful leverage, but they, too, are divided, largely over Social Security. Minority Leader Robert C. Byrd (D-W.Va.) will offer a plan that includes full cost-of-living increases for Social Security; Sens. Lawton Chiles (D-Fla.) and Ernest F. Hollings (D-S.C.) have a separate plan that includes a six-month benefit freeze.

While Dole's record so far has been uneven, he apparently is banking on winning in the end when it's all-or-nothing on his compromise, when the issue is not a choice among spending cuts but yes or no on the last chance to make a dent in deficits.

Meanwhile, the Democratic-controlled House is watching from the wings, content for the moment to let the Republican Senate point the way and take the heat.

A plan under study by Democrats on the House Budget Committee would cut deficits by about $47 billion, with deeper cuts in defense spending than the Senate has approved and no tampering with Social Security. But sources say the plan could change, depending on what the Senate does; in other words, the stronger the Senate plan, the stronger the House plan.