The Beavers’ 2-1 victory owed much to Chris Dickson’s double.
But the result was a huge team effort the manager said - even if there were late nerves from the Hampton players.
The south west London club move to within three points of the National League South play-offs as the Wings missed the chance to up the heat on leaders Torquay.
McCann told the club’s video service: “It was a really good result for us.
“It owed a lot to the dedication and determination of the players on a tricky day weather-wise.
“The level of effort and will to win from the boys was clear for all to see.
“Welling are a very good side and they didn’t play to their full potential - but a lot of that was down to us.
“We have had some bad games in the last few weeks. The one against Concord was a real mess but this was a really strong performance.”