The victim was airlifted to Wellington Hospital this morning after suffering serious head injuries in the crash, which happened minutes after a brawl broke out outside the pub.
The brawl, between 10-15 people, started just before 2.20am, and within the space of about four minutes, the man was hit by the car, and the driver fled the scene, a police spokeswoman said.
"Thinking of you bro, keep on fighting. We all know you're a tough bastard, you got this. Miss you, wishing you and the family the best," one person posted on the victim's Facebook page.
Another said she had been "thinking of you all day" and was "sending love to you and your family".
"Putting all my energy into you brother," another person said.
The car involved is described as a later-model, dark blue BMW, and may be missing a wind-screen wiper. The front, right headlight is possibly damaged.
St John territory manager John Stretton said the man was transported to hospital with serious head injuries.
A duty nurse manager confirmed just before 10am the man was in a critical condition.
Since being transferred to Wellington, his condition has been downgraded slightly.
CIB and the Serious Crash Unit are investigating the scene this morning.
Police would like to hear from anyone who is able to identify the car or driver, or any witnesses to the incident who have not yet been spoken to.
Please call Whanganui Police on 06 349 0600 if you can help.
Information can also be provided anonymously via Crimestoppers on 0800 555 111.
