Republican presidential candidate Sen. Marco Rubio speaks at a town hall in Marshalltown, Iowa, on Jan. 6, 2016.
Patrick Semansky—AP
January 13, 2016

A super PAC supporting Marco Rubio released an ad Wednesday taking shots at Jeb Bush’s struggling campaign.

Paid for by Conservative Solutions PAC, the ad fires back at Bush for previous jabs at Rubio, calling his campaign a “train wreck” for spending so much to little results. The super PAC supporting Bush, Right to Rise, released an ad Tuesday accusing Rubio of flip flopping on important issues. That ad also poked fun at a pair of heeled boots Rubio wore on the campaign trail.

In response the Conservative Solutions PAC ad claims that Rubio is the only candidate Bush—or Democratic front-runner Hillary Clinton—have to fear, touting his record on immigration and and calling Rubio an “expert on national security.”

Bush is in fifth and Rubio is in third in the race for the Republican presidential nomination, according to an average of national polls compiled by RealClearPolitics. Bush and Rubio, who shared a mentor-mentee relationship until things turned sour on the campaign trail, will be face-to-face Thursday at the next Republican presidential debate.

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