Trump rips Santorum after he wins in three states

Real estate mogul and reality TV star Donald Trump said Wednesday that he had nothing against former Pennsylvania Sen. Rick Santorum, but needed someone to explain why he was running for president.

"How can somebody who is a sitting senator run for the Senate as an incumbent and lose by 19 points to somebody else, and then say, 'well, gee, I just lost in Pennsylvania for the Senate by 19 points, now I'm going to run for president,'" Trump asked in a video uploaded to YouTube.

He said it would be like a high school student flunking out and then deciding to apply to the Wharton School of Finance.

On Tuesday, Santorum won the Missouri Republican primary and the Minnesota and Colorado caucuses. He previously won the Iowa caucuses.

Trump has endorsed former Massachusetts Gov. Mitt Romney. Democrats were quick to lampoon the ordeal, claiming the two rich businessmen both loved to fire people.

Watch video, uploaded to YouTube, below: