Clinton’s Surge Largest, Fastest in History of Polling : Survey: Commitment of converts described as shaky. New numbers show Clinton-Gore ticket edging Bush-Quayle 57% to 36%.

WASHINGTON —  Democratic presidential nominee Bill Clinton’s recent surge to the top of opinion polls represents the largest and most rapid shift in American voter sentiment in polling history, a Times Mirror Co. official said Thursday in releasing results of a national survey.

But the new poll also shows that the Clinton converts--many of them former supporters of Texas billionaire Ross Perot--are not strongly committed and could switch just as quickly to President Bush.

“Looking over polls of the past, we have never seen a shift this large this fast,” said Andrew Kohut, survey director of the Times Mirror Center for The People & The Press, which monitors public reaction to the news.

In the last six weeks, fully one-half of the electorate has changed its voting intentions in reaction to Perot’s decision not to run an independent campaign for the White House, and because its opinion of Clinton has improved.

Clinton has picked up the support of one in three voters who changed their minds since early June. In doing so, he has captured two-thirds of the former Perot backers, while Bush has taken about one-fourth; the rest are undecided.

Clinton also won over nearly one-sixth of the voters who said in June that they supported Bush--and three-fourths of those who said they were undecided.

However, an overwhelming majority of Clinton converts (71%) consider themselves only weak supporters of the Arkansas governor. Of those converts, 55% said their vote would be against Bush; just 40% said they would be voting for Clinton.

The results came from a Times Mirror survey in late July of 1,023 voters who also had been polled in early June. The second round of interviews was conducted to gauge how and why voters have changed their minds about the candidates. Times Mirror Co. is the owner of the Los Angeles Times and other newspaper, broadcasting and publishing enterprises.

The poll found the ticket of Clinton and running mate Al Gore leading Bush and Vice President Dan Quayle, 57% to 36%, in polling conducted from July 29 to Aug. 1. The same voters in June gave Perot 37%, Bush 32% and Clinton 27%. The margin of error was plus or minus 4 percentage points.

Two separate Times Mirror surveys conducted specifically to measure the staying power of Clinton’s bounce after the Democratic convention showed a somewhat larger and steady Democratic margin in each of the two weeks after the convention and Perot’s withdrawal from the race.

In polling conducted from July 22-26, Clinton led Bush, 58% to 31%; from July 29 -Aug. 2, the Democrat’s margin was virtually identical, 57% to 32%. The margin of error was plus or minus 5 points.

“There have been post-convention bounces in the past,” Kohut said, referring to the amount of improvement a candidate gets in polls after his party’s convention. “Right after the 1984 convention, (Democratic nominee Walter F.) Mondale had a pretty good lift,” giving him a 13-point lead over Republican Ronald Reagaon--who eventually won in a landslide. And Michael S. Dukakis came out of the 1988 Democratic Convention with a 17-point lead before he was trounced by Bush.

“But this is more than a bounce for Clinton,” Kohut continued. “This is a wholesale movement of the electorate. The reason is unique. We’ve never had a third-party candidate leading and then dropping out of the race. It has galvanized all of the anti-Bush support in a way that the wounded Clinton could not have, and has delivered it to him.”

Kohut said it may be significant that Clinton has been able to sustain his post-convention surge, in contrast to Mondale and Dukakis, who lost most of their new advantage within two weeks.

“No candidate has ever come back from a deficit as big as this one,” he said. “On the other hand, you have all these people thinly attached to Clinton.”

A statement summarizing the poll said, “Clinton’s recent converts come from all over the ideological and demographic map. Reminiscent of the Perot voters many once were, Clinton’s new supporters seem united only by their desire for change and dislike for George Bush.”

Although almost all recent converts (88%) say they now have a favorable attitude toward the Democratic nominee, as many as 43% had an unfavorable opinion of him in June and only one in five say they know “a lot” about what Clinton stands for.

In contrast, nearly half of those polled said that they know “a lot” about what the President stands for. But many went on to make negative comments in answering an open-ended question. The most frequent response (14%) was that Bush stands for the “rich upper classes and moneyed interests.” About one in 10 mentioned the President’s foreign-policy credentials and the same number mentioned the Persian Gulf crisis specifically. Eight percent mentioned the “negative effect on the economy.”

From June to August, the favorable ratings of the presidential candidates have gone in opposite directions. Thirty-six percent of those re-interviewed during the period viewed Clinton more favorably as time passed, while only 13% gave him a lower mark.

In contrast, 24% gave Bush a lower rating in the current poll, while only 15% gave him a better one.

Overall, Clinton’s favorable rating in the latest poll was 63% and his unfavorable, 35%. By contrast, fewer than half of the respondents had a favorable opinion of Bush: 47% favorable to 52% unfavorable.

In a separate survey released this week, MTV, the music television cable channel, said a national poll of young voters 18-29 showed Clinton with a 57%-33% lead over Bush. Barbara Bush received the highest favorable rating among the candidates’ wives with 71%, followed by Hillary Clinton with 54% and Tipper Gore with 33%. Voters were not asked about Marilyn Quayle.

Of those surveyed by the polling firm of Hamilton & Staff, “71% said Clinton would throw the best parties while only 16% wanted to party with Bush.”