Obama campaign stops in swing state Wisconsin

“I can afford to pay a little more and Mitt Romney sure can afford to pay a little more,” Obama said. “We don’t build the economy from the top down. We build it from the bottom up.”

The comments come one day after the release of Romney's 2011 tax return.

The rally’s crowd was estimated to be 18,000 and remained upbeat through the rain that started to come down during the event. Supporters would often boo at the mention of Romney, but Obama would cut them off.

“Don’t boo. Vote,” Obama said.

Earlier in the day, Obama attended two fundraisers in Milwaukee. At one of those events, the president hit Romney on the “47 percent” remarks he made at a private fundraiser earlier this year.

“We can't get very far if we're just writing off half the country as a bunch of victims, or presume that somehow they want to be dependent on government or don't want to take responsibility for their own lives,” Obama said.

“Because wherever I travel, folks are working hard. Folks understand everybody has got to take initiative. People understand that we're all responsible for ourselves. But people also understand that we've got obligations to each other.”

For more on Obama's remarks, click here.