Evan Soltas suggests increasing the Earned Income Tax Credit:

Liberal arguments for increasing the minimum wage have a fundamental flaw: They restrict the set of policy choices to either a minimum wage increase or doing nothing. That means they overlook the single most important federal policy for the poor: the Earned Income Tax Credit.

The EITC is a measure in the federal tax code to support the living standards of the poor without creating a “welfare trap” by diminishing the incentive to work. Economists widely consider the credit a success for reducing poverty while increasing employment. Created in 1975, the credit has been successively expanded in five times since. It is now the nation’s largest anti-poverty transfer program.