Democratic presidential hopeful John F. Kerry pledged Wednesday to give working-class parents an additional $20 billion in subsidies over 10 years to help cover child-care costs, significantly expanding existing programs.

The Massachusetts senator -- as part of his effort to focus on the woes of the middle class this week -- said that if elected president he would raise the child and dependent care tax credit to cover as much as $5,000 in child-care expenses, an increase of the current $3,000 credit. The plan would also for the first time offer the credit to stay-at-home parents.

In addition, Kerry's plan would launch "School's Open 'Til 6," expanding federal after-school care for working families so that 3.5 million children would be served, instead of the 1.5 million now using the program.

"This is the most important work in the United States," Kerry told parents and teachers at a community center here that offers after-school care. "I don't get it, and I'm sure you don't either when you think of the choices that we make as adults in our country," Kerry said. "The wealthiest people in America are getting a huge walk-away-with-the-store tax break, but a whole bunch of kids who need to have after-school adult input aren't getting it."

Kerry's campaign said that a couple earning $60,000 and spending $10,000 on child care for two children would get an additional $800 tax cut under his plan.

Spokesman David Wade said that Kerry's additional child-care credit would be "fully paid for by his proposals to close corporate tax shelters," which Wade said could yield $60 billion to $80 billion. As for the after-school program, Wade said that it would be funded by rolling back President Bush's tax cuts for people earning more than $200,000, and that it is money not already accounted for in Kerry's other spending proposals.

Bush campaign officials were quick to question how Kerry intends to pay for the expanded child-care programs. "All paid for by rolling back tax cuts for the wealthy, money that he has already spent 20 times over?" asked Bush spokesman Steve Schmidt. "This is a well that never stops giving."

Karen Kornbluh, director of the work and family program of the nonpartisan New America Foundation, said Kerry's proposal "shows an understanding that the economy and family issues are closely related, and I believe it will have broad appeal. We have a study that shows that a parent's stress level goes up when they don't have good after-school care and no job flexibility. It hurts productivity."

Kerry headed back to Washington on Wednesday afternoon for private meetings on Capitol Hill, fueling speculation that he will use the time to interview possible running mates. Kerry said he was meeting with his campaign manager, Mary Beth Cahill, to talk about the Democratic National Convention next month. Asked whether he was interviewing vice presidential candidates, Kerry said: "I don't talk about veep stuff; you know that. I'm very disciplined."

Kerry canceled an event in Detroit scheduled for Thursday so as not to interfere with the city's official celebration of the Pistons' upset win over the Lakers in the NBA Finals on Tuesday.

Kerry chose to test his new "middle class" economic message in one of the presidential campaign's battleground states, Ohio, where about 250,000 have lost jobs -- 160,000 of them in manufacturing.

Ohio is viewed by both campaigns as key to victory on Nov. 2, and both campaigns, as well as partisan interests, are pouring millions of dollars in resources into the state, in staff, field operations and advertising. Bush won the state by 3.6 percent in 2000, after Vice President Al Gore pulled out of Ohio to focus on Florida. Kerry campaign strategists say they will work on securing their base and trying to reach Ohio's high percentages of independent and swing voters.

Kerry drew enthusiastic supporters at two fundraisers and a rally in the state. He and the Democratic National Committee raised $1 million at two events here Tuesday, and about 2,000 people showed up in a steady downpour to listen to him speak for more than 30 minutes Tuesday night.

Marion Franklin Community Center, where he held a town meeting Wednesday, is one of 35 sites throughout the city that offers Capital Kids, an after-school program created by Mayor Michael B. Coleman (D). The program, Coleman said Wednesday, serves about 3,000 children citywide.

Visiting an after-school program at the Marion Franklin Community Center in Columbus, Ohio, John F. Kerry lets students trace his hands. He proposed launching "School's Open 'Til 6" for children of working parents.