Former first lady Barbara Bush began adding campaign donors to the family’s Christmas card list five decades ago, building an index-card file of well-heeled contributors who went on to serve as ambassadors, cabinet members and State Department advisers in the two Bush administrations.

Jeb Bush, who opened the door to a presidential campaign five months ago, is now reaping a record-setting haul thanks to a donor network that stretches back to his father’s election to Congress in 1966.

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