Holley vacuum secondary float stuck?

It could have been some crud stuck between the needle and seat preventing the needle from closing all the way. Since you "made a run", I'm guessing that you're talking a full throttle strip pass and that may have loosened up some rust or whatever from the fuel line or secondary float bowl fuel supply tube (depending on whether your Holley is a 4150 or 4160 series). I'd check my fuel filter for rust. If there is no rust, I would pull the secondary float bowl and check for old fuel residue, rust on the float pivot and float needle and seat condition.

Good luck!