Investors love dividends for many reasons, including the guaranteed income and the simple fact that many of these companies have proven business models and are more stable. But every once in a while, for various reasons, investors can find phenomenal stocks that have a lot of upside potential and pay a dividend — these are the stocks that can be huge winners over the long term. Ritchie Bros. Auctioneers (NYSE: RBA) and PetMed Express, Inc. (NASDAQ: PETS) fit this description for the following reasons.