CRONY

Familiar friend

• Ally

• Amigo

• Associate

• Back-room fellow

• Bosom buddy

• Bud

• Chum

• Close companion

• Close friend

• Close pal

• Cohort

• Compadre

• Confidant

• Friend

• Friend that goes way back

• Good buddy

• Henchman

• Intimate

• Long-time pal

• Mate, and a hint to the starts of this puzzle's four longest answers

• Old buddy

• Old friend

• Old pal

• One of the gang

• Pal

• Patronage beneficiary

• Political ally

• Sidekick

• A close friend who accompanies his buddies in their activities