President Barack Obama ridiculed a Republican Senate candidate on Wednesday for saying that the United States has "stage three cancer of socialism" because of federal student loans.

As The Huffington Post reported earlier, Rep. Todd Akin (R-Mo.) made the remark at a policy debate on Saturday, while arguing that the government should quit the student loan market completely.

Obama incredulously repeated Akin's comment at an event in Iowa City.

"I'm always interested in how folks talk about this issue," he said. "You've got one member of Congress who compared student loans -- I'm not kidding here -- to a stage three cancer of socialism."

Obama tried to repeat the phrase but broke up laughing.

"I don't know where to start? What do you mean? What are you talking about? Come on!" he implored, eliciting loud applause. "Just when you think you've heard it all in Washington, somebody comes up with a new way to go off the deep end."

Akin is one of three candidates seeking the GOP nomination to challenge Missouri Sen. Claire McCaskill in November. McCaskill is seen as one of the more vulnerable Senate Democrats up for re-election this year.