President Bush, campaigning for reelection in the potentially crucial swing state of Florida, went on the offensive today against his Democratic challenger as he accused Sen. John F. Kerry of adding a new twist to his position on the war in Iraq.

In a speech in Pensacola, the first of three stops in Florida before he takes his campaign to the Southwest, Bush mocked the Massachusetts senator for saying Monday that he stood by his October 2002 vote to authorize waging war in Iraq.

While campaigning in Arizona, Kerry had responded to Bush's challenge to him to answer whether, "knowing what we know now," he would still have voted in support of invading Iraq. The original rationale for the war, the purported threat to the United States from weapons of mass destruction held by Saddam Hussein, has evaporated in the face of U.S. failure to find stockpiles of such weapons nearly a year and a half after the invasion.

"Yes, I would have voted for the authority," Kerry said. "I believe it was the right authority for a president to have." But he said he would have used the authorization more effectively than Bush has done, and he said Bush should explain why he engaged in a "rush to war" based on faulty intelligence and "without a plan to win the peace."

Reacting to Kerry's statement, Bush said today, "And now almost two years after he voted for the war in Iraq, and almost 220 days after switching positions to declare himself the anti-war candidate, my opponent has found a new nuance. He now agrees it was the right decision go to into Iraq."

Bush continued, "After months of questioning my motives and even my credibility, Senator Kerry now agrees with me that even though we have not found the stockpile of weapons we all believe were there, knowing everything we know today, he would have voted to go into Iraq and remove Saddam Hussein from power. I want to thank Senator Kerry for clearing that up. Although there are still 84 days left in the campaign."

Bush told the crowd of about 10,000 supporters that he was seeking reelection "because we must continue to work with our friends and allies around the world to aggressively pursue the terrorists and foreign fighters in Iraq and Afghanistan and elsewhere."

The president also remarked on his nomination of a Republican House member from Florida to take the helm of the CIA, telling the crowd, "Today I nominated a fine Floridian, Congressman Porter Goss, to head the Central Intelligence Agency."

Some Democrats have criticized the nomination as a partisan political move. Retired Adm. Stansfield Turner, a former CIA director who supports Kerry, charged today that it was aimed at helping Bush "win votes in Florida" in the November election.

Florida, which swung the 2000 election in Bush's favor when he won there by 537 votes, is among the states that are considered up for grabs this year. With 27 electoral votes, it is one of the larger battleground states.

After campaigning in Florida, Bush flies to his ranch in Texas, then heads to New Mexico, Arizona, Nevada, California, Oregon, Washington state and Iowa. He is scheduled to return to the White House Saturday.

Kerry campaigned today in Las Vegas and criticized Bush's plan to bury nuclear waste at Nevada's Yucca Mountain.

During the 2000 election campaign, Bush had expressed opposition to storing spent nuclear waste in the mountain 90 miles northwest of Las Vegas, and he narrowly won the state over Democratic candidate Al Gore. But a year after taking office, Bush declared the mountain an environmentally safe burial site for nuclear waste now stored at dozens of other places nationwide.

Kerry said today that the Bush administration is threatening the security of Nevada residents and endangering thousands of other Americans with a plan under which more than 50,000 shipments of nuclear waste "would travel just yards away from homes, hospitals, parks and playgrounds in states across this country" en route to Nevada.

"Yucca Mountain to me is a symbol of the recklessness and the arrogance for which they are willing to proceed with respect to the safety issues and concerns of the American people," Kerry told community leaders, Washington Post staff writer Jim VandeHei reported. "When John Kerry is president, there will be no nuclear waste at Yucca."