A pollster's view of why Dukakis has lost his lead

``Phenomenal.'' California pollster Mervin Field uses that word to describe the swift, coast-to-coast shift in public opinion during the past month in the 1988 election campaign.

Mr. Field, who collects data state by state on the presidential contest, says that over the past few weeks, Michael Dukakis has lost his once commanding leads in a number of key states, including California.

Just before the Republican convention, Mr. Dukakis had an edge in 24 states with 353 electoral votes (270 are needed for election).

That base has shrunk to 14 states with 132 electoral votes, while George Bush is ahead in 19 states with 156 electoral votes, he says.

Though many analysts say the momentum now lies with Mr. Bush, Field says some of the largest states, with a total of 250 electoral votes, are still tossups.

Field's nationwide survey finds that after a summer marked by rapidly changing public opinion, various regions of the country are returning to their customary political habits.

Thus, such traditionally Democratic states as Minnesota, West Virginia, and Rhode Island are solidly in the Dukakis column, according to the most recent data. Others, such as New York, Massachusetts, Wisconsin, Maryland, Oregon, and Hawaii, are leaning Democratic.

At the same time, after some initial Republican concern, states like Florida, Indiana, New Hampshire, Wyoming, and Alabama appear firmly behind Mr. Bush.

The state-by-state survey shows where the real battlefields will be:

1.California. Democrats like pollster Peter Hart say they can't win without it. But Bush, with Republican Gov. George Deukmejian at his side, stumps California so often he almost seems to be running for state office.

2.Texas. Bush is ahead, but a recent poll put him just three points in front - not enough to be comfortable.

3.The big, Northern industrial states. In the tossup group are Illinois, Ohio, Michigan, Pennsylvania, and New Jersey. If Bush wins just two of those, Dukakis could be hurt. They comprise a vital Democratic target area, needed as a counterweight to Bush strength in the South and the Rocky Mountain West.

Over lunch in San Francisco, Field sought to explain the wild gyrations in public opinion this summer.

As the summer began, polls showed Dukakis running very strongly. But those polls were actually not about Dukakis, Field says. They were ``a referendum on Bush.'' It is well documented that people are ``not enthralled'' with Bush, he says, so in June and July, Democrats appeared to be running away with the race.

But there was an important caveat: Voters might change their minds once they got to know Dukakis.

``The Dukakis page was unwritten,'' he says. Public opinion about the Democratic nominee was unformed. ``And unfortunately for Dukakis, since the Democratic convention, the entries have been more negative than positive.''

Field explains:

``The public was ready to turn their backs on Bush, and ready to pin their hopes and aspirations and love and ardency on Dukakis. But he has not received it.

``The first reason is the Bush attacks. The attacks themselves shouldn't have done this to Dukakis because if you're in a campaign, you know you're going to get attacked. Your ability to anticipate attacks, respond to attacks, is really a great opportunity.

Field says Dukakis has not handled the attacks the way John Kennedy did in 1960 when he ran against Richard Nixon.

``Nixon was all over Jack Kennedy, but Kennedy had a style and grace, and he just won the public over with humor and the way he blunted those attacks, and then went on the attack himself.''

He says Dukakis missed that chance.

``You can't condemn Bush for attacking Dukakis. That was fair game. But this was the great opportunity for Dukakis to demonstrate his personality. Instead, he was in sort of semiwithdrawal, running around Springfield and North Attleboro, Mass., and just really missing the point,'' he says.

Field suggests the nation is now entering a new phase of the campaign where voters will begin directly comparing the candidates on issues and personality - ``the strengths and weaknesses of each.''

``I would say the next three weeks are critical,'' he says.