Original meaning is "spell" but has been transferred to meaning "luck" (or more commonly "bad mojo" as in "bad luck")

The word originally means a charm or a spell. But now its more commonly said meaning sex appeal or talent.

N.
1. Self-confidence, Self-assuredness. As in basis for belief in ones self in a situation. Esp. I context of contest or display of skill such as sexual advances or going into battle.
2. Good luck fetish / charm to bolster confidence.
3. ability to bounce back from a debilitating trauma and negative attitude

your sex appeal, the magic you posses over the opposite sex, the way you present yourself

1- What keeps Mike Myers going on.
2- The one who tries to stop Power Puff Girls from saving the day.
3- A person's charm.

= Personal magnetism
Mojo will make one seem and feel sexy, virile, appealing, invincible and in control etc.
Alcohol or love usually awakes the mojo.
When ones mojo is working, it often results in flirting and heavy socializing with the opposite sex (or whatever prefered).

That quality, often elusive, that sets a person apart from everyone else. The word "magic" could, almost without exception, replace "mojo" it in all of its contexts, sentences, and/or applications.

Your cool/style essence.