When civil-rights groups fretted about the ability of minority voters to get to the local Department of Motor Vehicles to pick up a free state-issued ID card, Governor Haley created an 800 number to offer free rides to anyone who couldn't afford the transportation.

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Now this may not seem relevant until you consider that some credit card and other systems authenticate callers by the same last four digits of the card plus the caller ID from their originating phone number.

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If your phone is compatible, you'll need to decide whether you want to get your phone unlocked so that it can accept a local SIM card -- the ID chip that carries your local phone number.

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To use a card at checkout, a cashier can either scan the card's bar code from the smartphone or type in the member's ID number.

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