on someone's coattails

on someone's coattails

Also, on the coattails of. Owing to another person's popularity or merits. For example, He won the cabinet post by hanging on the senator's coattails, or He was elected to office on the coattails of the governor. This expression, with its graphic image, dates from the mid-1800s, when coats with tails were in fashion.
See also: coattail, on