Democratic vice presidential candidate John Edwards (search) on Sunday accused Republicans of an immoral attempt to divide the nation by taking partisan advantage of the Sept. 11 terrorist attacks.

Speaking to several hundred people at New St. Paul Tabernacle Church of God in Christ, the North Carolina senator criticized a Republican group's ad that portrays Democratic presidential candidate John Kerry (search) as soft on terrorism.

"The truth is they're trying to exploit one of our nation's greatest tragedies for personal gain. It is immoral, and it is wrong," Edwards said. "This isn't a Republican issue or a Democratic issue."

Edwards said everyone is united on doing whatever is necessary to protect the country from terrorism.

The ad, which is airing at least in Iowa and Wisconsin, shows Sept. 11 hijacker Mohammed Atta, Al Qaeda leader Usama bin Laden (search) and other terrorists, and shows pictures of terrorist attacks in Russia, Spain and the United States, including wreckage from the World Trade Center towers. It asks, "Would you trust Kerry against these fanatic killers?" and says "President Bush didn't start this war, but he will finish it."

The ad is paid for by Progress for America Voter Fund, an affiliate of a group created by Tony Feather, a longtime Republican consultant and former Bush aide. The group, like similar organizations on the Democratic side working to elect Kerry, operates independently from the Bush campaign and is barred from having contact with his advisers.

That that hasn't stopped Kerry's campaign from claiming the Bush campaign is behind the group's criticism.

Bush campaign spokesman Brian Jones said the president has called for an end to such attack ads by outside groups.

"Nevertheless, the Kerry campaign has continually played politics with the war on terror," Jones said. "Kerry's chronic vacillation regarding the war on terror raises serious questions about his character and his ability to lead during these extraordinary times."

Edwards commented a day after Kerry's campaign responded to the ad with one of its own, accusing President Bush and Vice President Dick Cheney of "despicable politics." The Kerry ad claims the Republican ticket is "using the appalling and divisive strategy of playing politics with the war on terror, a strategy that undermines the efforts to combat terrorists in America and puts George Bush's own ambition ahead of the national good."

Edwards was following up with an appearance later Sunday in Lewiston, Maine. His visit to Michigan followed two campaign stops in the state on Saturday by his wife, Elizabeth Edwards.