Romney’s problem was that he was so risk-averse he hesitated to stand on his principles when there might be political blowback. He resisted Paul Ryan’s desire to campaign in urban neighborhoods, because there were few Republican voters in those neighborhoods. Instead of defending Ryan’s entitlement reforms, he turned the tables on Democrats to accuse them of supporting cuts in Medicare through the president’s health care law. Politics always wins out over policy—it’s simply a question of by how much.

Jeb Bush’s fundamental challenge is how firmly he will stick to his principles, even when they run against his political self-interest. Early on, Bush has won plaudits for pledging to stick to his beliefs on comprehensive immigration reform and the Common Core educational standards. More recently, he suggested that American officials should “politely” ask illegal immigrants who have overstayed their visas to leave—received by some as an olive branch to the Right. Asked about immigration on Wednesday, he focused on border security and criticized President Obama’s executive order legalizing some illegal immigrants in the country.

And there’s an internal debate within the GOP, even within the reform movement, over whether it’s better policy to aggressively cut the rate of everyone’s taxes or to tweak the tax code to provide benefits to certain disadvantaged groups. Yuval Levin, one of the conservative movement’s leading intellectual voices, has led the charge for targeted tax breaks and subsidies for families with children and middle-class households. Marco Rubio, Bush’s potential rival for the nomination, has been a leading advocate of many of these ideas. But other conservative reformers believe that focusing on targeted groups undermines the goal of a flatter, fairer tax.