Sen. Bernie Moreno (R-Ohio) joined Sen. Elizabeth Warren (D-Massachusetts) in proposing to raise the payroll tax cap so people with higher incomes pay more into the program. The GOP concession on taxes comes as lawmakers begin to confront a Social Security shortfall so large and so imminent that the party’s traditional demand for curtailing benefits is unlikely to suffice. In just six years, millions of Social Security recipients will absorb a 22 percent cut in benefits unless lawmakers provide an immediate infusion of nearly $500 billion.