Kroger's ( KR) business may not be quite as exciting as Nike's is to consumers, but its stock has actually been more exciting in 2013. Shares of the grocer are up 64% since the first trading day in January. There's no question that Kroger is the best-in-breed grocery stock right now, but the firm's current valuation doesn't show it. >>5 Stocks Under $10 Set to Soar Kroger is a 130 year-old grocer that operates more than 2,400 supermarkets, 750 convenience stores, and 325 jewelry stores under a handful of popular brands. Those marquees include Ralphs, Fred Meyer, Kwik Shop and Turkey Hill in addition to the firm's namesake stores; Harris Teeter is set to join the mix later this year. There aren't many advantages in the grocery business, but Kroger has found the few that really work well. For starters, the firm manufactures almost half of its private label products itself, a level of expertise that cuts out the middleman on the fattest-margin offerings. Gasoline is another lynchpin of KR's success. The firm uses fuel as a loss leader to pull in customers at nearly half of its locations. While many peers have copied that strategy, the existence of gas infrastructure at such a large percentage of its locations gives Kroger some built-in advantages. In many cases, rivals don't have the option to add fuel to as many of their own stores. So, with rising analyst sentiment in Kroger this week, we're betting on shares of this Rocket Stock.