Jordan is charismatic. She is also new to Nick who has just moved to New York from the more placid midwest. She provides excitement. It doesn't hurt that she is very pretty and Daisy's best friend which puts her in proximity to Nick. I don't think anything in the story indicates that she had to make Nick pursue her; he was attracted to her. Toward the end of chapter 3, when Nick criticizes Jordan's driving and calls her "careless", she says, "I hate careless people. That's why I like you." Her admittion that she liked Nick, had an immediate effect on Nick. His narration says, "...and for a moment, I thought I loved her." Nick is willing to overlook her dishonest side because he sees dishonesty all around him. The last sentence of chapter 3 concludes: "I am one of the few honest people that I have ever known." Since dishonesty is everywhere, her dishonesty does not stand out; it is the norm.