The empire has struck back — a conservative coalition aired nearly 7,000 advertisements in the past week attacking anti-establishment candidate Donald Trump in a last-ditch effort to prevent the real estate billionaire from winning the Republican nomination for president.

Since last Tuesday, a whopping 76 percent of all attack ads in the presidential race targeted Trump, according to a Center for Public Integrity analysis of data provided by Kantar Media/CMAG, an advertising tracking firm.

The pro-Marco Rubio Conservative Solutions PAC aired about two-thirds of these ads. Rubio is fighting for his political life having staked his campaign on winning the Florida primary, which is a week away. The last/best hope for the Republican establishment, the U.S. senator must win his home state to have any realistic chance of staying in the race.

One ad titled “Fools” accounted for more than a third of those aired by the super PAC.