Plouffe denounced the GOP presidential nominee's recent attacks on President Obama about welfare, Medicare and the role of government in job creation. Plouffe appeared on ABC's This Week.
STORY: Dems face challenge in N.C.
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"Right now, their campaign is built on a tripod of lies," Plouffe said. "A welfare attack that is just absolutely untrue. The suggestion we're raiding America -- absolutely untrue. And then this whole 'we can build it' nonsense.' "
Plouffe and other Obama advisers and top Democrats fanned out across the networks, appearing on Sunday talk shows as their party prepares to formally nominate Obama and Vice President Biden. The Democratic National Convention officially begins Tuesday in Charlotte.
Public opinion polls show Obama and Romney are basically neck-and-neck, with the race hinging on the outcome in about a dozen battleground states -- including North Carolina, where Obama won in 2008.
Plouffe, who ran Obama's campaign four years ago, said Romney's team will "pay a price." One example referenced by Plouffe: The Romney campaign has been saying that Obama wants to "gut" welfare by offering waivers to states seeking flexibility in meeting work requirements. That claim has been debunked by Factcheck.org and other independent organizations.
"On welfare, it's absolutely untrue," Plouffe said. "Everyone's who's looked at it is outraged that they're making this. ... These waivers strengthen work. You'd have to get 20% more work in the state to even qualify (for a waiver)."
The Romney campaign, meanwhile, alerted reporters to comments made by Plouffe and Obama strategist David Axelrod, pointing out that neither answered direct questions on Sunday shows about whether Americans are better off than they were four years ago.
