Sen. Cory Gardner (R-CO) is questioning how GOP frontrunner Donald Trump could defeat the Islamic State (ISIS) after he seemed unable to figure out the Colorado delegate process.

“How on earth are you going to defeat ISIS if you can’t figure out the @cologop convention?” the Colorado senator tweeted.

Gardner took to Twitter unleashing a series of tweets blasting Trump for claiming that the Colorado delegate selection was a fix after Sen. Ted Cruz (R-TX) swept nearly all the delegates at the state GOP convention: