President Obama on Sunday scaled back his claim that Republicans are taking foreign money for their campaigns, using slightly more ambiguous language at a rally in Philadelphia after GOP strategists warned Democrats against telling “baseless” lies to win votes.

Democrats had been directing their criticism at the Chamber of Commerce and other GOP-supporting groups. But after the latest Democratic National Committee ad outright claimed “it appears they’re even taking secret foreign money to influence our elections,” White House senior adviser David Axelrod acknowledged that “no one knows” where the money is coming from.

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Obama, speaking at a Philadelphia rally Sunday, hammered the campaign finance theme but left open the question of whether anybody is violating U.S. law by using foreign money.

“There’s no question the other side sees a chance to get back in the driver’s seat,” Obama said. “They are being helped along this year by special interest groups that are spending unlimited amounts of money on attack ads … just attacking people without ever disclosing who’s behind all these attack ads. You don’t know. It could be the oil industry. It could be the insurance industry. It could even be foreign-owned corporations. You don’t know because they don’t have to disclose.”

Read More: Fox News

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