ITV is to monitor live viewer reaction to the debut election debate tomorrow (April 15) through social media for the first time.

The Prime Ministerial showdown kicks-off at 8.30pm and will be streamed exclusively online at http://www.itv.com/electiondebate, providing the centre piece for a raft of audience interaction.

A viewer reaction graph will appear on the stream, charting the opinion of a specially selected panel of people watching the debate. ‘The Worm’ tool will register approval, disapproval or neutral feelings constantly throughout the show.

ITV will also host an online chat about the debate, where commentary, key quotes from the leaders and user views will be posted on a moderated feed, as well as contributions from ITV News correspondents. There will also be online polls where quantitative feedback will be monitored.

In addition, social networking sites Twitter and Facebook will provide a forum for viewers to vent opinion.

The comments of 5,000 Twitter users will be monitored on a “sentiment tool” developed by political aggregator Tweetminster, while a Facebook Live application will allow users to share views that appear on itv.com and on their Facebook friends’ news feeds.

“This is a truly historic occasion and we’re really excited to be the only site able to offer, not only a live stream of the debate, but the opportunity for our users to share their views and opinions both on ITV.com and across social networks such as Twitter and Facebook,” said Ben McOwen Wilson, director of online and interactive at ITV.

Yesterday, ITV announced that Thursday’s News at Ten will deliver instant viewer reaction to the election showdown. The bulletin will air directly after the debate and feature the results of a poll of more than 1,000 viewers.