In the current low-interest rate environment, many financial firms are struggling to grow top-line revenue -- this has not been the case at Discover Financial Services (NYSE:DFS) and Capital One (NYSE:COF). Since the financial crisis, both companies have consistently grown revenue and outpaced the broader market. 

Despite their recent successes, both companies appear to have long growth runways and may present investors with an opportunity to ride the growing trend from a cash-based global economy to electronic. In this video, Motley Fool financial analyst David Hanson discusses these two companies and why recent returns shouldn't deter investors from looking into these stocks.