Sarah Palin endorsed Christine O'Donnell, a Republican candidate for senate in Delaware, who has repeatedly insinuated that her primary opponent Rep. Mike Castle is gay.
Earlier this month, a firm until recently employed by the O'Donnell campaign released a video promoting the "rumor" that Castle was cheating on his wife with a man. O'Donnell has continued to imply that her opponent is gay, in addition to standing by her opposition to masturbation and her belief that viewing pornography constitutes infidelity to one's spouse.
As for why the former Alaska governor made the endorsement, according to Salon, "Palin did this either because O'Donnell's campaign manager worked with former Tea Party candidate Doug Hoffman, whom Palin previously endorsed, or because of the Tea Party Express. Either way, O'Donnell will probably not win Joe Biden's old Senate seat."