Congresswoman Alexandria Ocasio-Cortez of New York, one of the most influential voices among young liberals and a rising Democratic star, plans to endorse Sen. Bernie Sanders, I-Vt., for president and appear with him at a rally on Saturday, according to two people with knowledge of her plans. Congresswmoan Ilhan Omar, D-Minn., another member of the “Squad” of four liberal congresswomen, also announced late Tuesday that she was backing Sanders. The surprise endorsements are a political coup for Sanders, who has been fading in the polls and faced growing questions about his age and health. Before Tuesday’s Democratic debate, he had been sidelined from the campaign trail for two weeks by a heart attack.