Trump's deal-making instincts and Cuba's economic desperation may be pointing toward the same place: an economic opening that keeps the Castro government in place, trades investment for stability, and lets Trump declare a historic victory. Cuba expert Michael Bustamante thinks Trump "might be willing to take that deal any day of the week."

Cuba has signaled it could accept that. Its terms are simple: no interference in the political system, no demands on who stays in prison. But Bustamante says the political calculus is brutal for the rest of the room. Trump has repeatedly cited Cuban American voters as central to his Cuba policy. He has appointed Cuban Americans to key diplomatic roles, including Secretary of State. An economic deal that leaves the Castro regime untouched would be a very hard sell to that community, and could define Rubio's political future in Florida.

"Does he go along with it, and how does he sell it to his own community?" Bustamante asks of Rubio. Trump, who doesn't have to run again, might not care. But for Rubio, and for the Republican coalition in South Florida, the stakes are very different.