David Zalubowski/AP Photo

COUNCIL BLUFFS, Iowa - Kicking off his campaign tour through Iowa, President Obama today wasted no time attacking Mitt Romney's new running mate, accusing Rep. Paul Ryan of blocking aid to ranchers and farmers who have been hurt by the severe drought.

"I am told that Governor Romney's new running mate, Paul Ryan, might be around Iowa the next few days," Obama said. "He is one of the leaders of Congress standing in the way. So if you happen to see Congressman Ryan, tell him how important this farm bill is to Iowa and our rural communities."

Paul Ryan appeared later in the day at the Iowa State Fair.

"We've got to put politics aside when it comes to doing the right thing for rural America and for Iowa," Obama said to applause from the roughly 4,000 supporters gathered in Bayliss Park.

The fresh line of attack is part of a broader effort by the president to cast Romney's VP pick as obstructionist and responsible for the partisan gridlock in Washington.

"This weekend my opponent, Mr. Romney, chose as his running mate the ideological leader of the Republicans in Congress. And I've got to tell you, I know Congressman Ryan. He's a good man. He's a family man. He is an articulate spokesman for Governor Romney's vision. But the problem is that vision is one that I fundamentally disagree with," Obama said.

The president continued to road test his attacks against the Romney-Ryan ticket as he accused his opponents of wanting to end Medicare "as we know it" to pay for a tax cut for millionaires and billionaires.

Obama is spending three days in Iowa, trying to recapture support in the state that catapulted his presidential bid in 2008. Ryan is also campaigning in the Hawkeye State today on his first solo trip since joining the Romney campaign.

In addition to attending seven campaign events over the course of the bus tour, the president revealed he also plans to stop by the state fair, although the visit is not on his official schedule.

"Michelle has told me I cannot have a fried twinkie," Obama joked. "But I will be checking out the butter cow. And I understand this year there is a chocolate moose. So I'm going to have to take a look at that if I can."

Some things have changed, however, since Obama campaigned at the fair four years ago. "The last time I went to the state fair, Secret Service let me do the bumper cars … I wasn't president yet, so I could do that, but not this time," he said.

Reacting to the president's speech, the Romney campaign said "no one will work harder to defend farmers and ranchers than the Romney-Ryan ticket."

"After nearly four years of failure, it's no wonder that Barack Obama returns to the state that launched his presidential campaign with nothing more than broken promises and false attacks. Iowans deserve better. As president, Mitt Romney will strengthen middle-class families in the heartland, create jobs, and turn our economy around," Romney campaign spokesman Ryan Williams said in a written statement.

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