US retailers are on edge as they enter the crucial holiday season marked by consumer angst. But Walmart's confidence has not been shaken. While many stores are wary about their year-end sales, Walmart's dominance in the US retail sector may help it be a holiday season winner, drawing in low and higher-income shoppers alike as they grapple with an uncertain economic outlook. The retail giant on Thursday reported US sales that beat analysts' expectations, rising 4.5% during the three months to 31