In the e-mail, Ms. Cast described in detail the pain she endured as a young adult and the difficulties she faced publicly acknowledging her sexuality. At the end, she pointedly asked him to donate between $100,000 and $200,000 to the referendum cause. “Jeff, I suspect you support marriage equality,” she wrote. “I beg you not to sit on the sidelines and hope the vote goes our way. Help us make it so.” She hit “send” and waited. Two days later, on Tuesday, she received a reply while in a car with her family. Recalling that moment, she said she had to read it out loud twice to make sure she had read it right. “Jen,” the e-mail said, “this is right for so many reasons. We’re in for $2.5 million. Jeff & MacKenzie.