After his Super Tuesday success in seven states, there is an increasing air of inevitability about Mr Trump securing the nomination and a growing sense of chaos in the Republican party.

"Looks like two-time failed candidate Mitt Romney is going to be telling Republicans how to get elected". "I have a better chance of winning in OH than he does in Florida".

While Trump apologized for referring to Rubio as a "lightweight" before, he kept knocking Rubio as "little Marco" in another not-so-veiled attack at the other man. He's playing members of the American public for suckers.

WASHINGTON, D.C. - Who do you think won the Republican presidential debate on Thursday night?

Mr Cruz, from Texas, said Mr Trump was part of the problem, not the solution, as he had used government power for private gain. Ryan said Trump's more controversial ideas "disfigured" conservatism, and McCain voiced concern about Trump's "uninformed and indeed unsafe statements" on national security.

He was hammered nearly from the start - not only by senators Marco Rubio and Ted Cruz, but also by Fox News' aggressive questioners and their slides and charts.

Mr Trump said: "I've supported Democrats and I've supported Republicans, and as a businessman I owed that to my company, to my family, to my workers, to everybody to get along". Both states have winner-take-all contests and if Trump should win the two, it could be impossible to stop him from gathering the majority of delegates needed to lock down the nomination ahead of this summer's GOP convention.

Trump - who has repeatedly threatened the possibility of launching a third party bid should he feel that the party is treating him unfairly - also said he would back whoever the party crowns. "And let's be clear, nothing I have ever said comes anything close to what Donald Trump says regularly on a daily and routine basis".

Rubio, seemingly amused by the new nickname he's earned, accused Trump of being incapble of having a substantive policy debate. According to Twitter's stats, Trump gained the most followers during the debate, followed by Kasich, Democratic frontrunner Hillary Clinton, Cruz, then Rubio.

Romney suggested that voters support Kasich in OH and Rubio in Florida to peel off enough delegates to block Trump.