Fox channels have mentioned the US congresswoman Alexandria Ocasio-Cortez for 42 consecutive days, a study has found. The 29-year-old liberal star received at least 3,181 mentions in six weeks from Fox News or its sister Fox Business, according to research by Media Matters for America, a not-for-profit media watchdog. The finding will reinforce perceptions that Fox, owned by media mogul Rupert Murdoch, is obsessed by Ocasio-Cortez, portraying her as a radical socialist who threatens the American way of life.