Providing proof of domicile in the United States is critical for most people when submitting Form I864, Affidavit of Support. If you want to sponsor someone for a family-based green card, you need to provide proof of a U.S. domicile in your Affidavit of Support (Form I-864).Typically, in order to claim US domicile, the Affidavit of Support sponsor must be residing in the United States. You must reside in California for more than one year (366 days) before you will be eligible to be classified as a resident for tuition purposes. In the event of USCIS document delays, the residence deputy will evaluate the available documents before issuing a determination. Does she claim to be a resident of California? â–¡Yes â–¡ No. Is she a U. S. citizen? Visit the office of the Tahsildar, Sub-divisional Officer, Revenue Department office, or District office in your respective area.