What do I do if the tax shown by Turbotax is over $2000. less than what the IRS tax table shows?

MY taxable income is $64,990. and the tax table shows the tax should be $7416.00 and Turbotax shows it should be $5261.  I don't want to submit this to the IRS without getting some explanation as to how this can so different and make sure I am paying the correct amount.