Numbers fell online for the second leaders debate with tweets dropping by more than 22% and almost 8,000 less people taking part, but slightly predictable given that the debate was only on digital TV, which was always going to hit numbers.

According to Tweetminister the total number of tweets for the second debate was 142, 795 down from 184,396 first time around. The number of people tweeting fell by a similar amount dropping 7,693 to 28,790.

My guess is part of that fall was due to the fact that the debate was only on digital TV.  That had a very goodnight with a combined live audience of 4 million viewers across Sky News, BBC News 24 and Sky3, but was never going to compete with the 9.4 million who tuned in for the first terrestrial broadcast on ITV1.

My guess is that when the debate returns to terrestrial TV for the final debate on BBC One the numbers will rise again both in terms of viewing and social media.

Tweetminister’s online sentiment scores pointed to a draw showing: Cameron: 3.1 (-0.2 from starting score), Brown 3.1 (no change) Clegg 3.1 (no change). That seemed to tally with what a lot of people were saying online: Brown did better, Clegg was no longer an unknown quantity and Cameron failed to break through — unless you’re the editor of The Sun and the Daily Express.

On Facebook where traffic and activity was also down it had Clegg winning over  users with a poll of more than 20,000 putting the Lib Dem leader as the winner on 48%.

Interesting to note that other self selecting online polls like Channel 4′s also had Clegg as the big winner (Cameron as the big loser) while the weighted polls from Sun/YouGov and Guardian/ICM had had Cameron and Clegg as the winner respectively, but with less clear margins.

Facebook users also gave Brown strong peaks of positive feedback during the debate on the Facebook dial test confirming his improvement since first time around. Mercifully, he dumped the “my friend nick” schtick.

While the numbers were down last night the social media campaign continued to evolve. Labour distributed this online ad via bloggers and mainstream media journalists who were tweeting and/or live-blogging during last night’s debate.

The party had thousands of supporters engaging via the debate dashboard on its homepage last night who were a captive audience for distributing and sharing material like this. That’s kind of cool it shows how it is continuing to develop and adapt.

Although not if you’re Mark Borkowski, of Borkowski PR, who writing on MediaWeek.co.uk today insists that: “The parties have yet to find a dialogue or an unmashable idea and they feel clumsy and fumbling online. Ironically, given both Labour and the Tories hired Obama election strategists, Nick Clegg won the debate because the others seemed as though they were doing political karaoke.”

And no surprise to hear David Kershaw, chief executive of the Tories’ creative agency M&C Saatchi say something similar: “It’s a fallacy that online has replaced offline in terms of media communications.”

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