I have w-2 income and my wife just began a position in Dec ‘17 (she will have a 1099 for 2017). Can we file for the childcare tax credit? We have 4 dependents under 10

My wife has been a stay at home mom all year and has no earned income to date. We have four young boys and have probably spent over $10,000 in child care expenses. My wife was just offered a position in December 2017 for part-time work as a contractor. She will have received earned income before the end of 2017. Can we claim the child care tax credit since both of us technically have income now?