Barack Obama, in a bold appeal to religious voters, announced Tuesday that he would expand President Bush's program to award federal grants to faith-based groups.

Stressing that he believes "deeply" in the separation of church and state, the presumptive Democratic presidential nominee said the funding needs to be available to religious groups that are doing charitable, secular work -- such as reforming ex-offenders, feeding the hungry and rebuilding New Orleans.

"I believe that change comes not from the top-down, but from the bottom-up, and few are closer to the people than our churches, our synagogues, our temples and our mosques," Obama said after touring the Eastside Community Ministry in Ohio.

"That's why Washington needs to draw on them. The fact is, the challenges we face today ... are simply too big for government to solve alone."

But the Illinois senator made clear he was not endorsing Bush's program as it exists today.

He said that poverty programs were "consistently underfunded" under Bush's Office of Faith-Based and Community Initiatives, which administers such grants. He cited reports that said the program was used to promote "partisan interests," and said as a result smaller congregations and groups were left out of the running for government money.

Obama said his program would not be a "photo-op," and that he'd make sure small faith-based groups are educated on how to apply for federal dollars.

"I'm not saying that faith-based groups are an alternative to government or secular nonprofits. And I'm not saying that they're somehow better at lifting people up," Obama said. "Make no mistake, as someone who used to teach constitutional law, I believe deeply in the separation of church and state, but I don't believe this partnership will endanger that idea."

He said he would re-name the program the Council for Faith-Based and Neighborhood Partnerships.

"The new name will reflect a new commitment," Obama said.

John Dilulio, the former director of Bush's faith-based program, released a statement Tuesday praising Obama for his commitment.

"Senator Barack Obama has offered a principled, prudent, and problem-solving vision for the future of community-serving partnerships involving religious nonprofit organizations," he said. "Especially in urban America, all the empirical evidence continues to show that local faith-based organizations can make a measurable civic difference."

White House deputy press secretary Tony Fratto said Bush continues to value the faith-based initiative, adding: "If the future potential presidential candidates support it, I think that's something that we all would be very happy about."

Earlier in the campaign, Obama was dogged by criticism for telling a group of California donors that rural voters sometimes "cling" to religion and guns out of bitterness. He has since fought accusations that he is out of touch with working-class voters.

Obama talked about faith Tuesday as part of a series of events focused on American values leading up to the July 4 holiday. He talked about patriotism Monday and is expected to discuss national service later in the week.