The distribution is included in gross income; there is no exclusion in the law for using retirement account funds for this purpose. However, because you are over age 59½, there is no 10% early distribution penalty. Younger participants taking 401(k) withdrawals for home-buying costs are subject to penalty. The exemption from the 10% penalty only applies to withdrawals from IRAs for first-time homebuyers, and only up to $10,000.
Items directly reducing income. Personal deductions such as for mortgage interest, state and local taxes, and charitable contributions are allowed only if deductions are itemized on Schedule A, but deductions such as for alimony, capital losses, moving expenses to a new job location, business losses, student loan interest, and IRA and Keogh deductions are deducted from gross income even if itemized deductions are not claimed.