ASHINGTON - It's the Brigadoon of American politics, that magical zone where a candidate and a campaign message somehow click with the electorate and lure the voters to the polls in droves.
John McCain inhabits that special place now. And the era of the vanishing voter seems, for the moment, to have given way to a reawakened electorate, turning out in record numbers in state after state.
The question is: Will it fade away, like the mythic village of the Broadway musical? Or is there something real going on, something instructive about the 2000 campaign and the state of American politics? The excitement and high voter turnout have some political professionals wondering if the Arizona senator has tapped powerful hidden currents in the electorate.
''I'm struck by the high level of interest and engagement in this election,'' said Kellyanne Fitzpatrick, a Republican pollster. ''The voters are like a jury ... who all of a sudden are coming together, imbued with a higher sense of purpose.''
Other specialists are not so certain, or are unwilling to make a judgment based on the evidence of five weeks of contests. But their preliminary conclusions, while replete with caveats, are nevertheless intriguing.
The McCain phenomenon is for real. The vote in Michigan confirmed what the New Hampshire and South Carolina results suggest: that the Arizona senator has brought something special to the campaign, drawing independents and Democrats to the Republican primaries in record or near-record numbers.
''I think there is one source of excitement in this thing, and it is John McCain,'' said Thomas Patterson, who co-directs the ''Vanishing Voter'' project at Harvard University, an ongoing study on voter turnout.
New Hampshire had a record turnout of 396,000 voters, up from 302,000 in 1996, with all that growth attributable to GOP participation. (About 20,000 fewer Democratic votes were cast this year than in 1992, the last contested primary.) Michigan's record turnout of 1.3 million voters was up from 524,000 in 1996. And South Carolina's 565,000 voters was a doubling of the 276,000 who voted four years ago. In Iowa, where McCain did not actively campaign against Texas Governor George W. Bush, turnout declined from 1996 levels.
The turnout figures are particularly impressive because they follow reports of Americans being turned off by politics. Turnout in 1998 was the lowest in more than 50 years.
''There is no question that in three states McCain has mobilized people, to some extent outside the Republican Party, and that the party regulars, feeling threatened, have mobilized people against McCain, and that has produced record turnout,'' said Curtis Gans, the director of the Committee for the Study of the American Electorate.
''He is getting good marks and drawing in independents and Democrats and moderate Republicans for a) being authentic, which means not like President Clinton and b) for not being quite as much a captive of the Republican right and c) because in his ideas for reform he is reflecting some of the frustration the country has with politics,'' Gans said.
The anecdotal evidence speaks volumes as well: Witness the tens of thousands of voters who have changed their registrations to participate in the Massachusetts Republican primary. ''It is a positive loop,'' said Bill McInturff, the McCain campaign's pollster. ''Huge turnouts create enormous attention, you end up leading the national news, more people get interested and it keeps on building. It is animating the entire electorate.
''I wish I could say we were geniuses. But to be honest with you, it is blowing us away, way past anything we anticipated,'' McInturff said.
''My niece in Wayland, is 18 years old, and just registered Republican. Given her Democratic family lineage, there is no way she would be registering as a Republican to vote for Bush - it's McCain,'' he said.
''I don't know if it happened by dumbness or design,'' said Fitzpatrick, but it did. It worked.''
The McCain phenomenon may be temporary. Brigadoon vanished with the dawn, and American history is littered with candidates who caught the public's fancy but could not keep it. Wendell Wilkie, Eugene McCarthy, Gary Hart, John Anderson, Paul Tsongas, and Ross Perot all had their moments.
''If the McCain phenomenon means we have a candidate who is ... breaking through the thick, cynical barrier that most nonvoters have put up, then that could bode well for the November election,'' said Northwestern University professor Jack C. Doppelt. ''But I don't think you can make the leap that this is the case.
''You may indeed see McCain galvanizing nonvoters, but as with Bill Bradley, Ross Perot, or Jesse Ventura, it may be just a momentary allure that dissipates,'' said Doppelt, the author of a recent book on voter turnout.
McCain is playing outside the box. By targeting a new universe of voters, taking advantage of the Internet and running as a reform candidate, McCain is tapping forces that may play important roles in this year's election, and in the future of US politics.
Like Minnesota Governor Jesse Ventura in 1998, and Democrat Bill Bradley this year, McCain has pioneered the tactic of raising funds and appealing to young and independent voters via the Internet.
The political use of the Internet is at its infant stage, and not to be overestimated. Just one out of 10 Internet-using voters in Harvard's ''Vanishing Voter'' study spent any part of their day at a political Web site.
But the potential is there. Cisco Systems CEO John Chambers told a Brookings Institution seminar here this week that 90 percent of those who use the Internet vote, and 71 percent of Internet users ages 18 to 27 say they would vote if they could do so on the Web.
Lost in the news of McCain's Michigan victory Tuesday was a historical footnote. For the first time - in the Arizona Democratic primary - American voters cast their ballots over the Internet. Chambers predicted that by the year 2004 a majority of the 50 states will have Internet voting, while Patterson guessed that in the next two presidential elections ''the Internet will pick up a lot of the resources now spent on TV ads.''
The Internet is a receptive medium for insurgents like McCain. The rule of Web-based politics, as in business, is that ''the fast will beat the slow, not necessarily that the big will beat the small,'' Chambers said.
The enactment of the motor-voter law, which makes it easier for people to register to vote, has added 7 million voters to the rolls since 1975, according to the Federal Election Commission. And in states like Florida and California, registrars report that the percentage of independent voters is rising with easy registration.
Today's independent voters are more engaged, discerning, and deliberative than their unaligned predecessors of a decade or more ago, said Fitzpatrick, giving someone like McCain a new universe of voters in which to operate.
McCain's message may be self-limiting. McCain may have reached out to a fresh universe of voters, but he now needs to build support within his party core.
''I want to give him credit. The one thing he has been right about, from the beginning, is that the way to reach young people is to appeal to something larger than their self-interest,'' said Gans. ''But whether that continues to have an appeal once the Democratic opposition starts defining him is an open question.''
And Patterson noted that, despite the media hullabaloo, the percentage of voters older than 35 who know who won the New Hampshire primary is just 60 percent, and that figure drops in half among voters younger than 35.
His opponents' negative ads, and a more skeptical press corps, will inevitably strip the shine from the McCain campaign, Doppelt said. ''The deadening of the process,'' he said, will bring McCain back to earth. At that point he will need Republican loyalists.
Will the Republican faithful embrace John McCain? It's still an open question, McInturff, the McCain pollster, said.
''In John McCain we have an American war hero who has changed the nature of how you campaign, with the straight talk and the Internet, and has an expanded Republican message,'' McInturff said.
''George W. Bush could have been such a candidate, but instead decided to be the messenger of the last generation in our party ... But he may still be the nominee.''
