WASHINGTON -- Sarah Palin has lost the magic. The defeat of her choice Tuesday in a Republican Senate primary in her home state of Alaska capped a primary season in which her favored candidates have stumbled across the nation. A referendum to restore Palin’s signature achievement from her time as Alaska governor, a state tax on oil companies, was also headed toward defeat following Tuesday’s voting, dealing a double whammy loss to Palin in her home state and highlighting her declining influence. Only four of the 15 congressional candidates endorsed by Palin nationwide this year have won their primaries, a...