TERRE HAUTE, Ind. — Barack Obama and John McCain brought the battle over who is better prepared to change Washington to a pair of states that will be critical to the November election, and they sought to win over voters eager to turn the page on eight years of the Bush administration.

At an afternoon rally yesterday at the county fairgrounds here, Obama proclaimed that McCain is captive to his party and unable to provide a clean break from Bush policies, calling the GOP nominee a creature of Washington and mocking his running mate, Alaska Gov. Sarah Palin, for flip-flopping on earmarks.

"Now think about this. This has come from the party that has been in charge for eight years," Obama told a crowd of about 800 in a 4-H arena. "They've been running the show. So don't be fooled. ... John McCain's party, with the help of John McCain, has been in charge."

In some of his most pointed remarks about Palin since she was named to the GOP ticket, Obama called her "a skillful politician" but added: "When you've been taking all these earmarks when it's convenient, but suddenly you're the champion anti-earmark person, that's not change. Come on! I mean, words mean something. You can't just make stuff up."

While Obama has made a message of change the cornerstone of his campaign, McCain has refused to concede that the Democratic nominee will bring it about. McCain has long touted his efforts to reach across the aisle and bring reform to Washington, and, by picking Palin, his aides think he sent a message that a McCain administration would bear little resemblance to that of the past eight years.

In accepting the Republican nomination in St. Paul, Minn., on Thursday, McCain cast himself as an experienced and dedicated agent of change. He echoed that theme before thousands of flag-waving supporters in Colorado Springs, Colo., yesterday morning and urged voters to "send a team of mavericks" to Washington.

"Let me offer a little advance warning to the old big-spending, do-nothing, me-first, country-second Washington crowd," McCain thundered, borrowing a line from his convention speech. "Change is coming!"

Palin, who has regularly drawn louder applause than McCain since being chosen his running mate, drew a roar of approval at the same event when she described McCain as a man who "doesn't run with the Washington herd."

She also took her first public shot at her rival for the vice presidency, describing Sen. Joe Biden, D-Del., as a relic of the Beltway establishment who will not push for reform.

"Senator Biden can claim many chairmanships across many, many years in Washington — and certainly many friends in the Washington establishment," she said. "But even those admirers would not be able to call him an agent of change."

McCain and Obama also squared off in front of a gathering of seniors yesterday morning, appearing by satellite at the AARP convention.

Obama told seniors that McCain would abandon them economically, tax healthcare benefits and "gamble" with Social Security and their retirement savings.

"Job shipped overseas? Tough luck. Pension disappeared? That's the breaks. No healthcare? The emergency room will fix it. You're on your own," Obama said yesterday.

Obama's remarks to AARP prompted a blistering response from McCain's campaign spokesman, who accused the Democrat of employing scare tactics and falsehoods to mislead people about the Republican nominee's positions.

McCain used his appearance before the group to argue again that he would be able to reach out to Democrats on Capitol Hill to tackle tough issues such as healthcare and the future of Social Security and Medicare.

"We have to sit down together, Republican and Democrat, and reach across the aisle, and I have that record," McCain said.