With three weeks left in their election campaigns, President Bush and Sen. John F. Kerry sharpened their focus on domestic issues today in a race that new polls show continues to be tight.

Bush campaigned today in Colorado Springs, Colo., before a scheduled flight to Arizona, where the third presidential debate will be held Wednesday night at Arizona State University in Tempe. Aides said Bush was concentrating more on domestic matters such as health care ahead of the debate, while attacking Kerry as a liberal whose health care plan would place most people on a government program.

Reflecting the Bush campaign's latest tack was the release of two new television advertisements blasting Kerry's health care plan. The ads charge that the plan will cost $1.5 trillion and "result in rationing of care, less access, fewer choices and long waits," the campaign said in a statement. "Their plan will empower Washington bureaucrats, not doctors, to make final health care decisions."

The Kerry campaign countered that Bush was blocking real health care reform after having pushed a Medicare bill last year that added $139 billion to the drug industry's profits by prohibiting Medicare from negotiating the cost of drugs.

"With premiums up 64 percent, prescription drug prices rising four times the rate of inflation and Medicare premiums making record gains, health care has put a serious dent into family budgets," Kerry spokesman Phil Singer said in a statement. "George Bush's answer to this crisis is to stand in the way of cheaper prescription drugs, block Medicare from offering lower prices to seniors and oppose real health care reform."

Bush, addressing a rally in Colorado Springs, said, "Much as he's tried to obscure it . . . my opponent has shown why he's earned his ranking as the most liberal member of the United States Senate."

The Democratic challenger, a four-term senator from Massachusetts, has dismissed that characterization, accusing Bush of throwing around "labels" that don't fit him.

Kerry was spending the day in Santa Fe, N.M., conferring with aides and honing his attacks on Bush's domestic policies, with particular emphasis on rising oil prices that he says reflect the administration's failure to implement an energy plan.

In Davenport, Iowa, Vice President Cheney today renewed the Bush campaign's criticism of Kerry over a remark on terrorism.

Cheney also commented that attacks last week on tourist resorts in Egypt's Sinai Peninsula were likely the work of the al Qaeda terrorist network. Israeli authorities also have blamed al Qaeda for the bombings in Taba, Egypt, which killed 33 people, many of them Israeli tourists.

Egypt had cautioned against a rapid assignment of blame for Thursday's attacks, and the U.S. government had not previously attributed the bombings to any particular group.

With Kerry avoiding public appearances today while huddling with his aides, his campaign issued a statement highlighting new reasons that "George Bush has totally lost touch with reality" in Iraq.

The campaign pointed to a report by the International Atomic Energy Agency that equipment and materials that could be used to make nuclear weapons are disappearing from Iraq, with entire buildings dismantled and sensitive equipment removed. The Kerry campaign also charged that, contrary to assertions by the Bush administration, U.S. military commanders on the ground in Iraq have requested more troops but have been turned down by higher-ups.

In one of the latest national polls, CBS News today had Bush leading Kerry by 48 percent to 45 percent, with 2 percent for independent candidate Ralph Nader and 5 percent undecided.

A daily tracking poll by Zogby International showed the race tied at 45 percent each for Bush and Kerry.

Today's Washington Post's tracking poll, which is based on a rolling average of three days of telephone surveys, gave Bush a 3-point lead among likely voters with a 3-point margin of error.

The debate preparations came against the backdrop of a controversy over the planned broadcast by a chain of television stations of a documentary that fiercely criticizes Kerry and accuses him of betraying Vietnam war veterans.

The Sinclair Broadcast Group has told its 62 stations to preempt regular programming and air a documentary, "Stolen Honor: Wounds That Never Heal," that features former Vietnam prisoners of war and other veterans denouncing Kerry for statements he made against the Vietnam War after returning from combat in that country.

Sen. Richard J. Durbin (D-Ill.) said on ABC's "Good Morning America" today that the broadcast would amount to "an illegal corporate contribution" by Sinclair, which he charged was "dedicated to a political agenda" rather than the public interest.

Durbin, one of 18 Democratic senators calling on the federal government to block the broadcast, said Sinclair uses the airwaves under a government license. For the company "to decide to use them for one political campaign is, frankly, wrong and violates the [Federal Election Commission] rule against corporate contributions to the Bush campaign."

Mark Hyman, vice president the Sinclair Broadcast Group, rejected the argument and said Kerry has been invited to appear on the program to rebut the POWs. He said on the same show, "They have a right to be heard, and we think this is an issue that's very newsworthy."

In a separate interview on CNN's "American Morning," Hyman dismissed Democratic arguments that the planned primetime broadcast before the election was an in-kind contribution to the Bush campaign. "If you use that logic and reasoning, that means every car bomb in Iraq would be an in-kind contribution to John Kerry."

He said the major television networks "are acting like Holocaust deniers, pretending these men don't exist."

Asked if there is bias at Sinclair against Kerry, Hyman said, "I certainly hope not. There shouldn't be."

He also said it was "absurd" to say Sinclair's stations should be able to decide on their own whether to air the documentary or not. "Just like Sears tells all of its stores, you will sell Craftsman tools, McDonald's tells all of its restaurants, you will have a sesame seed bun; that's the business we're in," Hyman said.

Addressing supporters in Iowa, Cheney said the Taba attack last week, "looks like it probably was an al Qaeda attack as well; we don't know for sure."

At a breakfast gathering at a restaurant in Davenport, the vice president also continued his criticism of Kerry's remarks that Americans would feel safer if terrorism could be returned to a "nuisance" level.

"When was terrorism only a nuisance?" Cheney asked, listing attacks on U.S. targets in 1983, 1988, 1993, 1996, 1998 and 2000. "Which one of those was a nuisance?"

Cheney, who will also appear today in Wisconsin and Minnesota, said the election will be a "referendum" on how to fight terrorism. And he repeated his assertion, which he acknowledged is "controversial," that al Qaeda was tied to Iraq's Saddam Hussein.

The commission that investigated the Sept. 11, 2001, attacks on the United States found no collaboration between the two, but Cheney said testimony by former CIA director George J. Tenet pointed to a "roughly 10-year relationship" between Iraq and al Qaeda.

Iraq "is the most likely place where there could have been a nexus" between a government and terrorists, he said. "The world is a whale of a lot better off with Saddam Hussein in jail, and we did the right thing taking him down and his government down."

Cheney's meeting in Davenport was with about 60 Republican faithful who were invited because they had volunteered or otherwise served the party. The vice president took four questions from the audience, but they turned out to be testimonials praising the administration.

"I just want to thank you for everything you've done," said the first questioner. The second said of President Bush: "Next to Jesus Christ he probably took the greatest load on his shoulder of any individual." A third said: "I don't think we hear enough positive things" about Bush's education policies.

Milbank reported from Davenport, Iowa.