Since the Republican presidential primaries began on Feb. 1 in Iowa, major super PACs have spent more than $40 million to attack Donald Trump.

Anti-Trump spending passed the $40 million mark on May 24, when Priorities USA Action (a pro-Hillary Clinton super PAC) spent $1.7 million on a TV ad buy against the presumptive GOP nominee. The week prior, Priorities USA Action spent $2 million on a separate ad buy.