The former Derby boss came to the club in October after a torrid start to the campaign under rookie David Weir and has began to turn around fortunes.
The Blades have lost just one of their last 10 games to climb away from the relegation zone in League One and that run culminated in a superb FA Cup win at Premier League Aston Villa last week.
Clough was nominated for December manager of the month, though lost out to Brentford's Mark Warburton, and he has earned the praise of Porter, is back in the fray having been frozen out under Weir.
"It's been great since he came in, results speak for themselves," Porter said.
"He has changed a lot within the club, it seems a more happy place.
"The lads seem to be buzzing more and that is having an affect on the field. There is a lot more togetherness as well and the results show that.
"There hasn't been many changes in the playing staff so obviously he is having an affect.
"Results have changed the mood, he's come in and changed a few things, I don't think we needed that much, but what he has done has done the trick."
Porter has been a key figure in the Blades' upturn in form, having scored four goals in 12 appearances since coming back from a loan spell at Chesterfield.
And the 30-year-old was delighted to renew acquaintances with Clough after working under him at Derby.
"I've played under Nigel before and he has been great for me here," he added.
"I wasn't getting much of a chance under the previous manager, so I am happy he has given me that chance and I am getting back to my best."