Disappointing earnings news helped push stocks lower. Best Buy plunged 11% as it said extended store hours and price-cutting could squeeze profit. Campbell Soup fell after reporting its profit slumped. The two stocks were the S&P 500’s biggest losers. Yet the index is up 25% so far in 2013, a run-up that has prompted some to call for caution. ‘We’ve had a phenomenal run, particularly in the last few weeks. I wouldn’t be surprised if we would pull back,’ said Alec Young, at S&P Capital IQ. Retailers were a focus Tuesday, but it wasn’t all bad: Home Depot rose 0.9% after it raised its forecast. TJX gained 1%; its income is up 35%.