Thomas Frank, in a Salon article comparing Pres. Obama to Jimmy Carter and discussing Rick Perlstein's new book on the '70s:
Like Barack Obama, Jimmy Carter was drawn instinctively toward austerity—keeping the White House thermostat down and advertising his personal devotion to domestic thrift by donning a cardigan in a televised chat on the energy crisis.
Felt compelled to leave this comment, even though it's hopeless:
Ahh -- the myth of the Carter "energy sweater." The "sweater" wasn't about turning down the thermostat -- he began wearing it shortly after inauguration to show he was a down home guy, in reaction to the pomp of Nixon's "imperial presidency." Sometime in the '80s it became a Republican meme that Carter was a wimp shivering in the White House rather than a manly energy squanderer, and the sweater's meaning transferred from "humility" to "thrift." Perstein's book should have clarified this but perhaps it didn't.