Rossi: Major differences exist between state and federal taxes

... from wages amounts you contribute to deferred compensation and retirement plans, other than 401(k) plans. This means IRA plans and Keogh plans are not deductible on your New Jersey return, leading to higher taxable wages than your Federal return. ...

http://www.nj.com/mercer/index.ssf/2013/04/rossi_major_differences_exist.html