WASHINGTON — Democrat Barack Obama warned supporters yesterday not to get "cocky" about his lead in polls, while Republican John McCain pressed on with his theme that his rival will raise taxes.

A day after their final debate, both presidential candidates visited battleground states to make their campaign arguments anew.

The Democratic nominee reminded New Hampshire supporters that surveys there in January had him ahead of rival Hillary Rodham Clinton, but he lost the primary.

"For those who are getting a little cocky, I've got two words for you: New Hampshire," he said in Londonderry, repeating a warning he gave to New York donors earlier in the day. "You can't let up or pay too much attention to the polls."

McCain, campaigning in Pennsylvania, echoed an argument he made at Wednesday's debate that Obama would raise taxes. He declared small businesses the winner of the candidates' matchup at Hofstra University, saying his economic plan would do more for them.

"The American people are not going to let Sen. Obama raise their taxes in a tough economy," he said.

ACTIVIST GROUP IN FBI FRAUD PROBE

WASHINGTON — The FBI is investigating whether the community activist group ACORN helped foster voter registration fraud around the nation before the presidential election.

A senior law enforcement official confirmed the investigation to The Associated Press. A second official says the FBI was looking at results of inquiries in several states, including a raid on ACORN's office in Las Vegas, for any evidence of a coordinated national effort.

Both officials spoke on condition of anonymity because the Justice Department forbids discussing ongoing investigations particularly so close to an election.

LOBBYIST DENIES MCCAIN AFFAIR

WASHINGTON — A telecommunications lobbyist who became part of an explosive story early this year about John McCain has broken months of silence to deny suspicions she was romantically involved with the Republican presidential candidate.

"I did not have a sexual relationship with Senator McCain," Vicky Iseman, 41, told the National Journal magazine.

Iseman was the subject of an article by The New York Times in February that said in 1999 McCain aides worried that the Arizona senator and the lobbyist may be having an affair. The newspaper did not publish any evidence of such a relationship.

VOTER ELIGIBILITY RULING APPEALED

COLUMBUS, Ohio — Ohio's elections chief has asked the U.S. Supreme Court to intervene in a dispute over whether the state is required to do more to help counties verify voter eligibility.

Secretary of State Jennifer Brunner, a Democrat, filed an appeal with the high court late Wednesday, her spokesman Jeff Ortega announced yesterday.

On Tuesday, the 6th U.S. Circuit Court of Appeals in Cincinnati sided with the Ohio Republican Party and ordered Brunner to set up a system that provides names of newly registered voters whose driver's license numbers or Social Security numbers don't match records in other government databases.

MCCAIN FINALLY VISITS LETTERMAN

NEW YORK — John McCain appeared on CBS' "Late Show with David Letterman" last night, telling the host "I screwed up" by canceling an earlier appearance on the show.

McCain offered his mea culpa shortly after being playfully asked by Letterman, "Can you stay?"

Letterman has kept up a relentless comic assault on McCain ever since the GOP presidential candidate canceled his Sept. 24 "Late Show" appearance to deal with the economy.

Yesterday McCain appeared determined to show up: He flew by helicopter from Philadelphia to New York after a weather delay grounded his campaign plane.