Let $G=(V,E)$ be a finite loopless graph, with parallel edges allowed, and let $c(G)$ be the number of connected components of $G$. Let $M(G)$ be its graphic matroid. Then $P_G(q)=q^{c(G)}\chi_{M(G)}(q)$, where $P_G(q)$ is the chromatic polynomial of $G$.