WASHINGTON – Republicans sent allegations flying yesterday over what Bush supporters call an effort by news organizations to mount an ambush of the president in the final days of the race for the White House by repackaging an old story about missing high-grade explosives in Iraq.

Senator Kerry mocked Mr. Bush for failing to address directly bad news about the war on terror, while the president scored the Democratic nominee for departing from the great traditions of his party on national security.

With a week to go in the bitterly fought contest, both campaigns pulled out more big names to help the presidential candidates energize their bases and woo undecided voters. The Republicans fielded Mayor Koch, who stumped in the must-win state of Florida and appealed to New York retirees there, and the Bush campaign said it plans to deploy Governor Pataki in New Hampshire, Delaware, and North Carolina tomorrow to stump for the president. The Democrats announced that a rock star, Bruce Springsteen, is joining Senator Kerry tomorrow in Wisconsin and Ohio – both among the battleground states likely to determine the winner of the election.

The campaign skirmishing over the war on terror came as senior Republicans expressed dismay at the administration’s failure to offer a consistent line in response to claims that 350 metric tons of powerful explosives disappeared from a military depot in Iraq after the American-led invasion. They faulted advisers to the Bush campaign for a lack of speed in reacting to the reports when they first emerged Monday in the New York Times and on CBS, and they pointed to a later NBC bulletin from one of its correspondents who had been embedded with the American unit that temporarily took control of the installation in question, Al Qaqaa, in April 2003, but did not find any of the explosives.

“The president’s team should have been quicker off the mark,” a Republican senator told The New York Sun.

The NBC bulletin, along with State Department briefings yesterday insisting the explosives weren’t at Al Qaqaa when American troops first toured the depot, directly contradicted the Pentagon, which said Monday the explosives were intact when troops from the 101st Airborne Division arrived the day after Baghdad fell. The inconsistencies aided Mr. Kerry in accusing Mr. Bush of neglecting to secure sensitive military sites in Iraq after Saddam Hussein was toppled. But it remains unclear whether the explosives were shifted or looted before coalition forces even arrived.

Undeterred by the deepening mystery about the explosives, Mr. Kerry pressed his case yesterday against Mr. Bush, accusing him of bungling the Iraq war. In a blistering speech in Green Bay, Wis., the Democrat said the president hid bad decisions and he scoffed at the Republican for avoiding commenting directly on the issue of the missing explosives, which was first raised in the Times following a leak from the International Atomic Energy Agency.

“What did the president have to say about the missing explosives? Not a word. Complete silence,” Mr. Kerry said. “Mr. President, what else are you being silent about? What else are you keeping from the American people?”

The Democratic nominee berated the administration for the discrepancies about the explosives, saying: “First they said they couldn’t guard the weapons caches because they had other priorities. Then they argued that losing the explosives wasn’t really that big a deal. Finally, at the end of the day, the White House just boldly declared that it just didn’t happen.”

Mr. Kerry added: “When the president is faced with the consequences of his own bad decisions, he doesn’t confront them, he tries to hide them. The truth is, President Bush isn’t leveling with the American people about why we went to war, how the war is going, or what he is doing to put Iraq on track.”

The Democrat said a stream of bad news coming out of Iraq showed the Bush administration was glossing over the reality of the situation there. Mr. Kerry’s argument received some support yesterday from Iraq’s interim prime minister, Ayad Allawi, who blamed American-led coalition forces for a weekend ambush by insurgents. About 50 recruits training to join the country’s National Guard were murdered. “There was great negligence on the part of some coalition forces,” Mr. Allawi said.

After launching his attack on Mr. Bush in Wisconsin, Mr. Kerry set off for Nevada, a state he hopes to snatch from the president, and New Mexico.

While Mr. Bush didn’t respond directly yesterday to Mr. Kerry about the issue of the missing explosives, his campaign spokesmen accused the Democratic nominee of using questionable material and exploiting a media conspiracy to launch an October Surprise on the GOP. They pointed to an admission yesterday by CBS’s “60 Minutes” show that it had intended to run the same story as the New York Times on the eve of Election Day but had to scramble and run the allegations on CBS News about the looting of the explosives Monday, once it became clear that the story would not hold.

The Bush campaign spokesmen also said the explosives story is a repackaged version of reports first run in April 2003.

A Bush spokesman, Steve Schmidt, said the new information exposed as “baseless and false” Mr. Kerry’s claims. “He said American troops didn’t secure the explosives, when the explosives were already missing,” Mr. Schmidt said. He also said Mr. Kerry “neglects to mention the 400,000 tons of weapons and explosives that are either destroyed or in the process of being destroyed in Iraq.”

A State Department spokesman, J. Adam Ereli, told reporters yesterday that American troops who arrived at Al Qaqaa after the fall of Baghdad did not discover the explosives that the atomic energy agency tagged before the war and the ones reported missing. “We did not find any explosives under seal. We did find some explosives that were consolidated,” he said.

Mr. Ereli insisted the administration did everything it could to secure arms caches throughout Iraq, but he conceded, “Given the number of arms and the number of caches and the extent of militarization of Iraq, it was impossible to provide 100 percent security for 100 percent of the sites, quite frankly.”

For his part, Mr. Bush avoided the developing row over the explosives yesterday and accused Mr. Kerry of choosing a path of “weakness and inaction” when it comes to terrorists. Speaking in Onalaska, Wis., the president said his rival had put himself “in opposition not just to me, but to the great tradition of the Democratic Party.”

He added: “The party of Franklin Roosevelt and Harry Truman and John Kennedy is rightly remembered for confidence and resolve in times of war and in hours of crisis. Senator Kerry has turned his back on ‘pay any price’ and ‘bear any burden.'”

The president appeared determined to stay on the economic message he had planned for his campaigning in the Badger State, showcasing his tax cuts and calling for them to be made permanent. Mr. Bush charged that the tax hikes Mr. Kerry has proposed for wealthy Americans would hurt small business owners and prevent them from creating new jobs. He said the economy is recovering and he concentrated on how Wisconsin is faring in his bid to win the state, arguing farm income is up and unemployment is down in the state. “We’re headed in the right direction here in America,” Mr. Bush said.

But as the president was speaking, a New York-based research group reported that an index of consumer confidence dropped in October for the third consecutive month. The decline was steeper than some expected.

The president, who lost Wisconsin and its 10 electoral votes by a margin of only 5,708 in 2000, appealed to conservative Democratic voters during a three stop bus tour in the western part of the state, urging them to cross over and vote Republican. Bush campaign advisers say they are confident that the Badger State will swing into the GOP column.

While Mr. Bush focused on Wisconsin, Vice President Cheney teamed up in Florida with Mr. Koch, a Democrat who has backed the president in the war on terror. “You can depend on George Bush,” Mr. Koch said at a rally in Palm Beach County.

The Bush campaign managed something of a coup in persuading Mr. Koch and Mayor Giuliani, who have clashed many times in the past, to agree to record a radio ad together supporting the president and urging Floridians to vote for Mr. Bush.