HILLSBOROUGH, N.H. - Republican John McCain is having quite a moment. He's rising in the polls. He's got major newspaper endorsements in Iowa and New Hampshire. And now he's getting help with this state's legions of independent voters from Joe Lieberman, the contrarian who was Democrat Al Gore's running mate in 2000.

"The Mac is Back," said a hand-painted sign on the wall of the packed American Legion post where Lieberman announced his endorsement yesterday, a newly optimistic tone after a bumpy campaign year for the Arizona senator.

The decision by the Senate's best-known independent to snub the Democratic Party could help McCain win a bigger share of the tide of independent voters who have been expected to flow to the Democratic field in New Hampshire's first-in-the-nation primary on Jan. 8.

Independents outnumber Republicans and Democrats here, and the state is key to McCain's hopes for the GOP nomination.

Support from a high-profile senator who almost always caucuses and votes with Democrats risks alienating conservative GOP voters, angry already at what they see as McCain's abandonment on immigration and campaign finance. Democratic leaders expressed their annoyance, too.

There was no doubt, however, about the Lieberman announcement's buzz effect - no small factor in a race now in the homestretch with a large field. The news injected energy and interest into the McCain campaign, still behind in the polls but glowing from a weekend of coveted newspaper endorsements: from the Des Moines Register in Iowa, where he is barely competing in the Jan. 3 caucuses, as well as from the Boston Globe and the Portsmouth Herald - both influential in New Hampshire. He'd already been endorsed by the New Hampshire Union Leader.

McCain also seemingly has enough money to stage a more serious play for South Carolina. He announced yesterday he is going on the radio there with a spot featuring the state's popular Republican Sen. Lindsey Graham - another of his Senate colleagues.

McCain's strategy, pared down after financial and organizational troubles earlier this year, now calls for winning New Hampshire and using that boost to lay claim to South Carolina.

Independents, who can vote in either party's primary in New Hampshire, are the wild card. They helped McCain beat George W. Bush here in 2000. McCain advisers are hoping for a repeat - but this time not followed by a loss in South Carolina and defeat for the nomination. *