* Rally ends 9-day losing streak, rises almost 4 pct * Synthetic prices pointing higher * Bulls points to tighter supplies NEW YORK, June 3 (Reuters) - ICE cotton staged its biggest one-day gain in over seven months and settled limit up on Monday as speculative investors piled back in to buy after prices sank to four-month lows at the end of last week. Bringing an end to a nine-day losing streak, prices jumped 2.5 cents per lb in the final 90 minutes of trading as speculators piled back in betting on tighter U.S. supplies with just two months until the end of the 2012/13 season. Traders saw no obvious trigger for the sudden surge late in the morning, but Ron Lawson, a partner at commodity investment firm LOGIC Advisors, said the market had finally woken up to the bullish factors that he expects to support prices. "You had nine days down and it ran out of selling. The U.S. is sold out. Australia is sold out. China's been buying. The only cotton left is certified stock," he said. The most-active July cotton contract on ICE Futures U.S. rose 3 cents, or 3.8 percent, to settle at 82.36 cents per lb, its daily limit price. That was its best one-day performance since October.