Hurricane Irene knocked out power to 2.5 million homes and businesses, forced two nuclear plants to shut and idled oil ports and refining as it advanced toward New York City early on Sunday. Mid-Atlantic coast states reported more power losses even as the hurricane spun northward and blackouts in Delaware, New Jersey and New York jumped. The category 1 hurricane made landfall in New Jersey before dawn with 75 mile-per-hour winds, dumping heavy rain and provoking storm surges.