Unfortunately, you can't. If you claimed the standard deduction on your federal deduction, you must claim the standard deduction on your Virginia state return.
Please see “ITEMIZED OR STANDARD DEDUCTIONS” on page 11 of 2017 Form 760 Residential Individual Income Tax Booklet for more information.
Yes, it is; however, be sure and test it in Turbo Tax if your itemized amount is relatively close to the standard. My itemized deductions were just short of the standard of $24,400 and by choosing to itemize, my NET tax refund went up 62%.
Shouldn't Turbo Tax check for you? My total returns doubled by itemizing on federal rather than the standard (and paying more). I went back and checked last years and I would have gotten a a significant amount back on my state rather than owing. Now I need to figure out how to update both my last years returns