CHICAGO (AP) — A former Chicago-area sheriff has emerged from a crowded Illinois Republican primary field to mount a long-shot challenge to U.S. Sen. Dick Durbin.

Mark Curran, Lake County’s former sheriff who had perhaps the most name recognition of all the candidates, said he ran because the political climate had changed and he believes Durbin is vulnerable in November. Durbin is the No. 2 Democrat in the Senate and was first elected in 1996 and has handily won each election since then.

He’s also extremely well funded with $4.5 million cash on hand.