The first of three debates saw Brown, Cameron and Nick Clegg go head to head for 90 minutes on ITV1, discussing issues such as immigration, policing, health and defence.
In a poll of 200 comms experts taken at an event held by Mandate in Westminster, 45 per cent of comms experts said they thought Brown had received the best media training, while 76 per cent believed Cameron made the biggest blunder.
Clegg received praise in today's media, with The Guardian leading with the headline 'Clegg the outsider seizes his moment in the TV spotlight' and The Daily Telegraph leading with 'Clegg's star rises in great TV showdown'.
Fifty-eight per cent of those polled at the Mandate debate changed their opinion of the political leaders after watching the TV debate.
Mandate Communications chief executive Sacha Deshmukh said: 'Everyone saw David Cameron poised in the starting blocks, but it seemed no-one saw he had tied his shoelaces together. He recovered slowly from some early blunders but by then Gordon Brown had established a consistent style. Alongside a strong performance from Nick Clegg, the Conservative leader was eclipsed.'
Some 62 per cent at the event believed this leader debate will have a major bearing on the outcome of the general election, while 80 per cent also said Tony Blair would have won the debate if he was still Prime Minister.
PRCA director general Francis Ingham said: 'A good start and a strong finish from Cameron, but the main part wasn't inspiring. He needs to do two things: to have a central theme that runs through and frames his arguments; and to show more passion for his cause. He'll go for the kill in rounds two and three - because he has to. Time to fire up the Quattro Dave.'
Meanwhile, Weber Shandwick head of public affairs Jo-Ann Robertson praised Brown for his 'statesman-like body language' and 'strong sense of humour'.
'He had a clear message and he delivered it in a calm, measured and authoritative way. There was obviously an element of expectation management, and the creepy smile made a few appearances,' said Robertson.
An audience of 9.9 million viewers watched the debate, figures showed today.
An average of 9.4 million people tuned in and the show had more viewers than the other four terrestrial channels combined at that time.