To appeal to a wider base of voters, Republicans will have to rethink their myopic focus on personal and corporate income taxes and look at ways to attack payroll taxes.

In a 2013 study, the Tax Policy Center estimated that 43 percent of Americans paid no income taxes (which was down from the 47 percent in a prior study that fueled Romney’s remarks). But the same study found that just 14 percent of households paid neither payroll nor income taxes, and two-thirds of those were elderly.

When combined, the payroll tax rate paid by workers is 15.3 percent. Though the tax is theoretically split among workers and their employers, TPC has noted that, “most economists believe that the employer’s share is fully offset by reduced wages and thus the entire economic burden of the tax ultimately falls on workers.”

|n 2012, combined payroll taxes cost more than income taxes for nearly 80 percent of middle-income Americans, according to TPC analysis, and 63 percent of all taxpayers. And this was in a year in which the rate was temporarily reduced by 2 percent as part of a short-term stimulus agreement.