Richard Ellis/Getty Images; EMMANUEL DUNAND/AFP/Getty Images

GOP presidential candidate Newt Gingrich this morning slammed Mitt Romney, calling him a "not a very convincing frontrunner" on "This Week."

"He is a long way from having closed out this race," said Gingrich, brushing off Romney's five recent Republican contest wins ahead of Super Tuesday.

Gingrich also went after his other rival Rick Santorum, saying he was "historically a labor union senator" from Pennsylvania. In his interview this morning, Gingrich also predicted he would win his home state of Georgia on Super Tuesday by a "bigger margin" than Romney won Michigan. He also said he would would Alabama and Mississippi.

"Big ideas matter. Twice in this process I have been the frontrunner in national polling," said Gingrich. "I think we have a chance to get back." he said.