As pollsters and consultants conducted post-mortems on the Tuesday night presidential debate, a fairly consistent pattern of agreement emerged on winners and losers, agreement signaling little change in the Republican contest but potentially significant developments in the Democratic race.

On the Democratic side, campaign specialists from both parties in the main agreed that the televised two-hour debate on NBC produced two net gainers, Massachusetts Gov. Michael S. Dukakis and Sen. Albert Gore Jr. (D-Tenn.), and two who suffered setbacks, Sen. Paul Simon (D-Ill.) and Rep. Richard A. Gephardt (D-Mo.).

Jesse L. Jackson received strong praise from almost all the campaign experts, including such Republicans as Douglas Bailey, who said Jackson is the only candidate prepared to present a larger vision to the voters, and Robert Goodman, who said he was strongly impressed by Jackson's willingness to take risks.

Among the six Republican candidates, the most widely held view was that Vice President Bush held his own by failing to make any mistakes, effectively maintaining his status as the front-runner. Sen. Robert J. Dole (R-Kan.) was credited with a performance improving the standard he set in the previous debate in Houston, but not enough to move significantly closer to Bush.

In addition, former Delaware governor Pierre S. (Pete) du Pont IV sharply improved in style and tactics, while Rep. Jack Kemp (R-N.Y.) received poor grades from the Democratic and Republican professional strategists.

Former television evangelist Marion G. (Pat) Robertson was widely viewed as continuing to come out a net winner because his smooth television performance undercut voter fears of the former preacher who believes that God speaks directly to him.

The debate, which NBC said was watched by 7.5 million people, was broken into four 30-minute segments. Democrats and Republicans separately debated foreign policy questions during the first two segments, and then discussed domestic issues during the last two segments.

The evaluations by campaign consultants and pollsters in some respects coincided with the findings of a controversial "people meter" survey of 100 Iowa caucus-goers, although the Iowa survey produced some internally contradictory results.

The strongest difference between the professional political experts and the Iowa survey of 40 Republican and 60 Democratic voters was over Bush's performance. "Bush showed extreme losses among the 40 Republicans in the {metered} audience on intelligence, judgment, and honesty," said Chris Wheeler, who ran the survey in which the 100 Iowa voters watched the debate on movie screen while they were connected by meters to a computer. Bush's ratings were most negative when he avoided directly answering a question about his role in the Iran-contra affair.

The Iowa voters agreed, however, with the experts that both Dukakis and Gore did well, and that Gephardt did poorly. "Within his own party particularly, Gephardt shifted in the negative direction significantly," Wheeler said.

While Simon, who is the front-runner in Iowa, lost a little standing in the pre- and post-debate analysis of the Iowa voters, the evaluation of his performance by the campaign professionals was much harsher.

Simon "lost some ground," GOP consultant John Deardourff said. When Simon was asked how he reconciled his support for a balanced budget with an $8 billion jobs program and expanded education initiatives, "he was not prepared to answer." Simon's answer to that question was, in part: "I've served on the Budget Committee in the House. I understand the figures. We can do it and we're going to do it. No question about it."

"It came through loud and clear that Simon was not giving specific answers," Frank Greer, a Democratic consultant who is not yet committed to any presidential candidate, said.

Some of the assessements of other candidates were:

Bush. "He didn't withdraw, he didn't cower in a corner, and he doesn't see anything mutually exclusive between being a strong leader and being leader," said Democratic pollster Harrison Hickman. "Unfortunately, the vice president did well. He is holding off the wimp factor longer than I thought he could," Democratic consultant Bill Hamilton said. The one consultant sharply critical of Bush was Geoff Garin, of Peter Hart Research, who said, "Bush looked like everybody's nightmare when he wouldn't answer {Alexander M.} Haig's question about Iran-contra. He was like a little schoolboy waiting for the bell to ring."

Dole. One of Dole's own advisers, who asked not to be identified, said "his closing was good, but most of the time he looked more discomfited than I expected. He just has not found a way to project the same sense of command that he does when he is on his feet in the Senate."

Deardourff said Dole "did a little better than in the Houston debate, but a marginal difference. It was not a case in which he closed the ground between him and Bush to any degree. Running in place is not going to get him where he wants to go."

Kemp. "He seemed a bit whiny; he didn't seem to be in the real debate," Greer said. "I forgot he was there," Hickman said. Goodman, however, argued that Kemp gained ground when he declared his support for pardoning Lt. Col. Oliver L. North and retired admiral John M. Poindexter for their roles in the Iran-contra affair. "Kemp was bold," Goodman said.

Gephardt. "He was demonstrating pretty sharp elbows that are not becoming on television," Deardourff said. There was a "sense that he talked more about leadership than he demonstrated leadership," Garin said. The two campaign strategists who liked Gephardt's performance are Charles Black and Roger Stone, both of whom are Republicans working in Kemp's campaign. Stone noted that in an exchange between Gore and Gephardt, "Gephardt still got the last word in."

Babbitt. Former Arizona governor Bruce Babbitt (D), who got terrible reviews after his performance earlier this year in a Houston debate, received mixed ratings Tuesday night. "Babbitt should shift to a radio format," Democratic consultant Carter Eskew said with some sarcasm. Bailey noted that Babbitt "is not a particularly skilled TV communicator," but when he physically stood up to declare his willingness to raise taxes to balance the budget, it may "turn out to be one of those memorable moments. He made his point."