Though Jay Gatsby and George Wilson are an unlikely pair for comparison in The Great Gatsby, they actually have several things in common.
First, both know what it's like to be poor. It's true that Gatsby has left those days behind them, but he was just as poor as George--if not more so--at the beginning of his life.
Second, both love a woman they can't have. A poor Jay Gatsby loves Daisy, a woman who embodies what it means to be rich. He had no chance of being with her at the time they fell in love. A poor George Wilson fell in love with and married a poor Myrtle Wilson; however, he never really had her love. From their wedding day, she was discontent and dissatisfied with her husband--the one who had to borrow his wedding suit. Wilson had no chance to win her love unless he made money, which he didn't.
Third, both suffered heartbreak. Gatsby's was a lifetime of yearning and longing for Daisy, followed by a short interlude of love with her, and ending with a tragic denial of the love he thought they shared. Wilson's was a kind of ignorance that Myrtle was so unhappy, followed by the tragic discovery that she loved someone else (or at least was with someone else), and ending with her sensational death.
Finally, they were both victims of Tom and Daisy Buchanan's careless lifestyle. Each of them lost their loves as well as their own lives to this self-absorbed pair, with various tragic moments in between.