The high-profile squabble among Republicans over the Iran-contra report appeared yesterday to have undermined the political benefits that GOP dissidents hoped to reap from their scathing rejection of the document as a partisan attack on President Reagan.

By heating up the politics of the issue, they also may have helped rekindle public interest in Reagan's role in the affair just as it was waning, many lawmakers and observers agreed.

Norman Ornstein, a congressional expert with the conservative American Enterprise Institute, and Thomas E. Mann, a political scientist with the more liberal Brookings Institution, agreed that the three Republican signatures on the majority report undercut GOP dissenters' contention that the majority findings were purely political.

Moreover, Ornstein said, "It's become much more of a story than it would have been without a minority report. The talk shows have the point-counterpoint they love so much. And the more it's a story, the more it winds up damaging the president."

What the public saw yesterday was not just a dissent by eight of the 11 Republicans on House and Senate Iran-contra investigating committees, who claimed that the majority report had drawn "hysterical conclusions" about the president's role in hopes of taking "partisan political advantage" of the affair.

It also saw an angry Sen. Warren B. Rudman (R-N.H.), vice chairman of the Senate panel, defending the majority report as bipartisan and denouncing his GOP colleagues' analysis as "that pathetic little report."

Rudman was joined in signing the majority report by Republican Sens. William S. Cohen (Maine) and Paul S. Trible Jr. (Va.). The minority report was issued by the six Republican members of the House panel and GOP Sens. Orrin G. Hatch (Utah) and James A. McClure (Idaho).

The Republican dissidents deprived the Democratic majority on the two committees of a claim to "It's become much more of a story than it would have been without a minority report."

-- Norman Ornstein

full bipartisanship for its findings, and there was little agreement between the factions over whether that dulled the impact of the Iran-contra probe.

Conservative Democratic Sen. David L. Boren (Okla.) expressed what may have been the prevailing view: that most Americans drew conclusions from the televised hearings last summer that are unlikely to be changed by either report.

"It's almost like the television commentator who tells people after a speech what they had just heard," Boren said. "The hearings were important," he added, "and I'm not sure the report will be."

Senate Minority Leader Robert J. Dole (R-Kan.) agreed in a carefully worded statement that "an initial reading does not seem to differ from what we learned at the hearings this summer: Some of the president's key advisers let him down by not keeping him properly informed." He did not mention the majority or minority report.

Sen. Daniel J. Evans (R-Wash.) said that, while the dissent may have undermined the report to some extent, "it's not very good politics for anyone to end up with two reports."

The appearance of partisanship in the two reports is blunted by the prominence of the three senators who supported the majority version, Brookings' Mann said.

"If you had a majority report and a unified Republican response, it would be one thing," he said. "But the prominence of the three Republican senators lends more weight to the report than would otherwise be the case . . . . It becomes more than just a Democratic attack on a Republican president."

But overall, he said, "the broad political effect {of the Iran-contra affair} has already registered," and the report is likely to contribute little to the political impact.

The dissent of the House Republicans and the two most conservative Republican senators came as no surprise in light of their defense of the White House during the hearings.

In addition, the House is more partisan than the Senate. House Republicans, in their 34th year of minority status, face continued Democratic control into the foreseeable future, and their defensive crouch has intensified since Rep. Jim Wright (D-Tex.) became speaker this term.

By contrast, the Senate operates more informally and collegially, with narrow majorities that have shifted twice in the last decade. Rudman and Cohen, in particular, have crossed party lines on such issues as budget reform and arms control. And the Senate, far more than the House, made it clear from the beginning that it intended a bipartisan pursuit of the Iran-contra affair.

"The only report that House Republicans would sign was a report that no Democrats would sign," Ornstein said. "The House is so partisan that there is just about zero chance you could get a bipartisan report on anything."

They "look for enemies almost everywhere," said Cohen, a former member of the House minority.