The campaign of GOP Florida Gov. Charlie Crist on Monday continued to try to demonstrate how former state House Speaker Marco Rubio (R) isn’t as conservative as he would like Senate primary voters to believe.

A release by the Rubio campaign on Dec. 5 particularly irked the Crist camp. That document, released ahead of President Barack Obama’s trip to Copenhagen to discuss climate change policy, touted how Rubio stood up to Crist on cap and trade during his time in the state House.

“Were it not for Marco Rubio, Charlie Crist would likely have succeeded in imposing an oppressive cap-and-trade scheme in Florida that would have deepened Florida’s economic crisis,” Rubio spokesman Alex Burgos said in the release. “As President Obama pursues the same type of job-killing, business-crippling cap-and-trade policies that Charlie Crist tried to impose, Marco Rubio offers Floridians reassurance that he’s the only candidate in this race with a proven record of standing up to this agenda.”