So, Jon Stewart, Dick Cheney and Lindsey Graham get on the subway…

Forget the old “walk into a bar” jokes — what happens when a former late-night TV host, a GOP presidential candidate and an ex-vice president walk into the Senate subway?

{mosads}Such an “only in Washington” scene unfolded Thursday on Capitol Hill, as Jon Stewart was eyed chatting up Sen. Lindsey Graham (S.C.) just as former Vice President Dick Cheney strolled by.

Stewart was in the Senate subway with a group of firefighters pressing for a reauthorization of health benefits for 9/11 first responders — a cause that has brought him to Congress’s door before. The former “Daily Show” host struck up conversations with lawmakers as they whizzed by, and started talking to Graham.

here is a blurry photo of Jon Stewart looking at the back of Lindsey Graham's head pic.twitter.com/FgRnZRoC5c

— Julian Hattem (@jmhattem) December 3, 2015

As the pair was gabbing, Cheney, who was at the Capitol for the official unveiling of his marble bust earlier in the day, passed by with an entourage. But a trifecta of unexpected chit-chat wasn’t to be — Cheney didn’t appear to make contact with the ex-Comedy Central host or the White House hopeful.

— Peter Sullivan contributed