Meanwhile, a pro-Cruz super PAC, Keep the Promise I, which released three new attack ads hitting Rubio on Sunday, was readying a seven-figure ad buy across the state on late Monday, according to a person familiar with the discussions. So far the super PAC has only inquired about rates, not purchased any ads. It is still debating internally over what media — talk radio, cable and broadcast — to hit and, more crucially, which of Florida’s vastly different media markets to play in, the source said.

If Cruz’s super PAC goes aggressively against Rubio in South Florida, it is clearly going for the kill. But any pro-Cruz ads that would air in more conservative regions, such as the Panhandle, could take more votes from Trump than Rubio.