2012 GOP nominee blasts 2016 GOP front-runner, refusing to endorse any other

Mitt Romney, the 2012 Republican presidential nominee, on Thursday ripped Republican presidential candidate Donald Trump as a "phony" and a "fraud" and urged Republicans to shun him.

However, Romney did not endorse any of the other three Republican candidates.

"Let me put it plainly: if we Republicans choose Donald trump as our nominee, the prospects for a safe and prosperous future are greatly diminished," said Romney in a rare public plea in a speech at the University of Utah.

"He is not the temperament of a stable, thoughtful leader. His imagination must not be married to real power," said Romney, condemning the GOP front-runner for "the greed, the showing off, the misogyny, the absurd third grade theatrics."

Romney, who had already ruled out his own presidential bid, shied away from endorsing any other Republican candidates still struggling in the field dominated by Trump, and his reluctance in picking his favourite candidate at this critical moment reflected the conundrum confronting the Republican party establishment.

"I would vote for Marco Rubio in Florida, for John Kasich in Ohio, and for Ted Cruz or whichever one of the other two contenders has the best chance of beating Mr. Trump in a given state," said Romney. "One of these men should be our nominee."

After winning three of the four early-voting contests in February, Trump further cruised to his nomination with big wins in Super Tuesday contests.

With 10 victories in total on hand, he further cemented his status as the undisputed front-runners of the party, leaving his rivals with increasingly long odds of overtaking him in delegates.

According to a New York Times delegate count, after his sweeping victories in February and on Super Tuesday, Trump won 319 delegates. His nearest challenger Cruz won 226 delegates, and Rubio, the junior senator from Florida who had picked out establishment endorsements and donors after Jeb Bush bowed out, got only 110 delegates.

To win the Republican nomination, a candidate must win at least 1,237 delegates.

After his limp showing on Super Tuesday when he won only the Minnesota Republican caucuses, Rubio and his team scrambled to prove to weary donors and disheartened supporters that the Republican mainstream resources should still rally around him, and on March 15, Rubio would face probably the biggest test for his candidacy during the nomination process when voters in his home state Florida would cast their ballots.

According to polls, however, Trump was leading the field with more than 40 percent of support, leading Rubio handily by double digits. Endit