I'm seeing the same issue while working on my state return. This could be a problem caused by Paylocity (our payroll company) because I see the same thing on both of my W-2s.
I can verify that when the W-2 is imported, it begins the employer's state ID number in Box 15 with the first 3 characters "MN ". If you open the VIEW tab from the Menu bar, you can then open FORMS and finally open the particular W-2 and see that TurboTax has broken Box 15 into two separate boxes (both labeled 15), one expecting the state abbreviation and the second looking only for a seven digit number. Unfortunately, as it imports, it fills the first Box 15 with the correct state abbreviation, but includes that same abbreviation and a space before the seven digit number in the second box.
You can correct this by going to Forms on the Menu bar and opening the problematic W-2 there. You can click and remove the "MN " from the second box 15; when you close the form it will have saved that change. Changing it in this way will propagate the correction through to the state forms as well.
