DES MOINES — Democratic vice presidential candidate Joe Biden turned his focus Monday to a faltering economy, claiming that Republican inattention to middle-class financial worries “is stunning” and shows how out of the touch the party has become.

“I’ve never seen a time when so many middle-class Americans are living with such anxiety,” Biden told a crowd of more than 1,000 at the Iowa State Fairgrounds in Des Moines. “I’ve never seen a time when so little was being done to lift them up.”

It was Biden’s first trip to Iowa since the state’s caucuses in January, when voters gave Barack Obama a key victory and effectively ended his own presidential campaign.

In his speech, Biden combined a fiery attack on Republicans with a populist message that it’s Democrats who working Americans can trust on the economy and taxes.

“We’re not going to raise your taxes. We’re going to end their tax breaks,” said Biden. “Middle-class taxpayers are getting three times the amount of tax relief from an Obama-Biden ticket than from a McCain-Palin ticket.”

While Biden fared poorly in Iowa’s leadoff caucuses, he campaigned often in the state and is a familiar presence after two runs for the Democratic presidential nomination. He dropped out even before the 1988 caucuses, and was one of the first casualties in this election cycle.

He was serving traditional running mate roles in his latest swing, combining slashing attack on Republicans with efforts to energize the Democratic base.

“It is stunning how out of touch this administration and John McCain are,” said Biden.

He derided McCain’s effort to cast himself as a change agent.

“I find it absolutely fascinating when John McCain and the Republican Party are claiming the mantle of change, after eight years of abject failure on foreign policy, after eight years of turning their backs on average Americans, John is going to change the culture of Washington,” Biden said.

Biden argued that if all of Bush’s tax breaks for the wealthy were ended “they’d still be paying lower taxes than they did under Ronald Reagan.”

He dismissed McCain’s effort to distance himself from a sitting president who is down in the polls.

“Let’s just look at it analytically,” said Biden. “On all these problems … I have not seen anything coming out of John McCain’s mouth or his running mate’s mouth that says to me he disagrees with this administration on a single solitary significant policy position. Let’s get serious here, do they think we’re stupid?”

Most polls have shown Obama with an edge in the competition for Iowa’s seven electoral votes, and his campaign has built a far larger organization in Iowa than McCain has established. After rallying at the fairgrounds, Biden was scheduled to attend a closed fundraising event in Des Moines.

Biden pointed to the rhetoric at the just-completed Republican National Convention as more evidence that working families should place their trust in Democrats.

“John McCain and Sarah Palin, if you listened at that convention, the silence was deafening on all the things that matter,” said Biden. “The Obama-Biden administration would literally cut taxes on 95 percent of Americans who draw a paycheck.”

Biden’s mission was to energize middle-income workers. His populist appeals focused on income while linking McCain to Bush.

“After eight years of this administration we find ourselves in a very, very deep hole,” Biden said. “I’m going to be talking a lot about retirement, our retirement plans and their retirement.”

Biden also gave a nod to politically savvy Iowa activists.

“You’ve seen all of us come and go, you’ve seen all the presidential candidates, you’ve heard all the issues,” said Biden. “I hope you can see from the convention that this thing with Barack is real. This is not something that’s made up.”