First Lady Tammy Murphy was born into a Republican family in Virginia, so it was only natural that she became a Republican herself when she came of age. But it’s fair to ask why she remained a Republican for most of her adult life, switching parties only in 2014, at age 49, as her husband prepared to run for governor as a Democrat. And she was no passive Republican. She was a true believer, judging by the scores of donations she made to Republicans across the country. She joined battles against several all-star Democrats, including Hillary Clinton, Frank Lautenberg, John Kerry and Al Gore. The…