Don’t believe the talk that the 2013 tax hikes nail only the highest earners. Lower- and middle-incomers are hit because of the payroll tax cut’s repeal. The effect of the expiration of the two-percentage-point drop in employees’ share of Social Security tax is being felt this month, as many workers see lower paychecks. An employee making $50,000 this year owes an additional $1,000 in payroll taxes, lowering his or her paycheck by about $19 a week. Individuals making under $100,000 wind up bearing more than 60% of the burden of this year’s payroll tax increase.