The Cruz campaign is taking direct aim at Rubios relatively sparse Florida operation and polls showing Rubio sharply trailing Trump, which one Cruz spokesman likened to a burning dumpster fire. Roman said Cruzs campaign wants to siphon off Rubios support and argued that the senator should drop out of the race.
Were making the case to his supporters: We agree with you, and Marco Rubio agrees, too, that he doesnt want Donald Trump to be the nominee,  Roman said.  Save yourself the embarrassment of losing your home state and let us consolidate the anti-Trump vote. 
In addition, the Cruz campaign is contemplating ramping up its efforts in Ohio which also has a March 15 primary in a bid to damage Ohio Gov. John Kasich, according to a person familiar with internal discussions. Cruzs campaign declined to comment on any plans for the state.
Together, the efforts make up a high-risk strategy to winnow the field and position Cruz as the last alternative to Trump. It is an approach that even some Cruz allies fear could backfire and aid in Trumps rise.
But Cruzs advisers say privately their modeling shows that even if Trump wins both Florida and Ohio, the senator from Texas has a better chance of securing the nomination than with Rubio and Kasich in the race. They are being bolstered by a surge of donations, including major contributions to a network of super PACs allied with his campaign.