The Club for Growth's Super PAC, Club for Growth Action, was particularly critical of Trump's candidacy, announcing a $1 million Iowa advertising buy against his campaign in September 2015. The Club for Growth Action was the first third-party group to spend significant sums against Donald Trump.[154] The Club for Growth announced a $1.5 million advertising buy in Florida in March 2016. The group's advertisements highlighted Trump's support for liberal policies, such as a single-payer health insurance system and tax increases.[155][156][157][158]
In March 2016, Politico reported that the Club for Growth PAC planned to deny congressional endorsements to any candidates who endorsed Donald Trump's presidential bid before the nomination was actually clinched. The Club's PAC noted that the warning did not apply to those who endorsed Trump after the May 3, 2016, Indiana primary.[159][160] Also in March 2016, the Club for Growth PAC endorsed Ted Cruz for president. The Club for Growth PAC had never previously endorsed in a presidential race. According to Club for Growth head David McIntosh, "This year is different because there is a vast gulf between the two leading Republican candidates on matters of economic liberty. Their records make clear that Ted Cruz is a consistent conservative who will fight to shrink the federal footprint, while Donald Trump would seek to remake government in his desired image."[161]