YRTLE BEACH, S.C. - Before they arrived here a few days ago, Senator John McCain and his aides were optimistic about South Carolina's Feb. 19 primary but keenly aware of the challenge ahead. Yes, Governor George W. Bush of Texas had a 20-point lead in the polls here, but there was time, they said.
''We've got 18 days,'' went the mantra.
Now, after trouncing Bush in New Hampshire and after three days in the Palmetto State, everything has been turned on its head. The poll gap has vanished, and McCain's audiences are so big here, they have overwhelmed organizers, cramming venues chosen when expectations were smaller. And the groups are even more adoring than McCain's Granite State throngs.
This wasn't supposed to happen yet.
''We were hoping to be 10 or 12 points behind by the time we landed in South Carolina,'' said John Weaver, McCain's political director. ''I don't like to believe polls, but I believe my eyes, and my eyes tell me we're very competitive.''
Now, instead of having two more weeks to grab the lead, McCain has two weeks in which to battle not to lose it.
McCain and his aides are jubilant over the events of the past few days, a giddy high only magnified by news that he will now be allowed to compete in the New York primary. The reeling Bush campaign, meanwhile, reportedly plans to convene a Texas meeting of top campaign officials to map out a new battle plan.
''They say the Bush campaign hit a bump in the road,'' McCain, flanked by two suits of armor, told a crowd of 2,000 at the Medieval Times theater restaurant yesterday morning, referring to Bush's concession speech in New Hampshire. ''I think it tore out the transmission!''
He has been using variations on that line most everywhere he has gone in the past few days. He used it at the rallies with college students, the first of which began in Greenville about 3 a.m. Wednesday, and ended, like the others, with a burst of confetti, flag-waving, and thumping music worthy of a president.
And again in the affluent community of Seabrook Island, where Bill Bradley supporter Nancy Dawe sent $100 to McCain ''to level the playing field.''
He also used it at the Georgetown Fire Station, where the crowd spilled out past the firetrucks and across the street.
''I came for the spectacle of it. He's really come on strong after New Hampshire,'' said Dan Stacey, 29, of Georgetown, who was standing on Prince Street outside the firehouse trying to catch a glimpse of the candidate. ''He merits attention. I just wanted a chance to see a hero.''
Since Tuesday night, McCain has been laying claim to a quality more closely associated with the Texas governor until now: electability.
''My message to Republican leaders is that we can win,'' McCain said Wednesday at a press conference in Greenville. ''This kind of motivation, this kind of enthusiasm that we've generated in New Hampshire we can generate here in South Carolina, will make for winning campaigns all over this country.''
There has been more of the heir-apparent about McCain since Tuesday night. Wednesday morning's orderly press conference was a rare event in a campaign more commonly characterized by press scrums. Lately, the senator has been more formal and upright on stage, swapping his usual pacing, and his white-knuckled grip of the microphone stand, for a less casual stance.
His speeches are far more consistent than those in the past, forgoing detailed descriptions of his policies in favor of more generalized, sharper, more predictable delineations of his major themes: campaign-finance reform, use of the surplus, respect for the military, and his credibility as a presidential candidate.
New Hampshire has given McCain more than what he often says is ''a megaphone'' for his ''crusade'' against the influence of special interests. It has given him a justification for his appeal to a wider audience than conservative Republicans, the traditional state primary audience. Over and over, he tells audiences here that his New Hampshire victory attracted new voters that the Republican Party has been coveting for years.
''On the way in, several independents and Democrats stopped me and said, `I'm voting for you,''' McCain said Thursday. ''My dear friends, these are the people we used to call the Reagan Democrats.''
But his campaign is defined by its underdog status, and McCain and his aides are making it clear that he is still the scrappy battler he always was. McCain, who says he feels more comfortable when he is slightly behind, told reporters on his bus yesterday that he was sure the polls would ''bounce up and down.''
He is still campaigning as the antiestablishment candidate. The campaign has busily launched preemptive strikes against claims made by Bush surrogates that McCain is too liberal.
At each event here, he has been introduced by US Representatives Mark Sanford or Lindsey Graham, who say McCain is a threat to the establishment. They say the establishment is out to get McCain by comparing him to Clinton, and calling him a liberal.
''Can you believe that?'' they ask audiences, which roar and laugh at the preposterousness of the idea.
Now it is Bush who has 14 days to regain an edge on McCain. And McCain's campaign, which got ahead in New Hampshire and had to hold the lead for six weeks, knows doing it again will take work.
''Our battle right now is to fight and scratch and claw for every vote,'' Weaver said. ''And that's what our schedule will reflect.
''You saw what happened in a matter of three days. The opposite can happen if we become anything but aggressive,'' he said.
