Each State can decide if they want only their portion reported as gross wages, or the total reported as gross wages. They might give credit back for the amount taxed by another State, or do it another way. That's why your $57k idea might not be correct. CO seems to use the Box 1 amount per your commentary.

"In the case of a part-year resident, any income that relates to that part of the year while he or she was a Colorado resident and any other income derived from Colorado sources are both subject to Colorado income tax."

https://tax.colorado.gov/income-tax-topics-part-year-residents-nonresidents

Income tax is prorated so that it is calculated only on income received in Colorado or from sources within Colorado.

https://tax.colorado.gov/part-year-and-nonresident

Hope that helps.