Republican vice presidential nominee Paul Ryan wrapped up his four-city campaign swing through Iowa with a rap against the current vice president, Democrat Joe Biden.

“Vice President Biden just today said that the middle class over the last four years has been ‘buried,'” Ryan said. “We agree. That means we have to stop digging by electing Mitt Romney the next president of the United States.”

Ryan made his comments during an afternoon rally in Burlington.

“Of course the middle class has been buried. They’re being buried by regulations. They’re being buried by taxes. They’re being buried by borrowing,” Ryan said. “They’re being buried by the Obama Administration’s economic failures.”

The Obama campaign issued a statement in response to Ryan’s remarks in Burlington, saying Biden has been “saying all year” that the middle class has been “punished” by the Bush era tax policies Romney and Ryan advocate.

Ryan began his bus tour through Iowa Monday night with a rally in Dubuque, then spoke to crowds in Clinton, Muscatine and Burlington today.

By Brian Crozier, KBUR, Burlington

Here are some photos from Paul Ryan’s stop in Iowa: