To ride on someone's coattails

To ride on someone's coattails - to have one's success dependent on that of someone else.

Example - "I don't think she would get promoted without riding her boss's coattails"

Image - http://imgc-cn.artprintimages.com/images/P-473-488-90/60/6067/JSZD100Z/posters/peter-c-vey-my-new-business-model-is-to-ride-on-the-coattails-of-somebody-else-s-new-new-yorker-cartoon.jpg