Opinion polls aren't the only way to get a sense of the issues, parties and personalities that people are interested in during this election. Taking a look at what people are searching for online can provide an interesting counterpoint to the more traditional measures. Certain developments lend themselves more to this kind of measurement than others and the recent party leaders' debate is a perfect example.

Insights for Search is a tool Google designed to allow users to compare the popularity of different terms in searches – ie what people are looking for – and all of the graphs in this piece were created with it. Google's more precise explanation can be found here. (One of the limitations of these tools is the lag that accompanies them. All these graphs measure up to Friday 16 April, the day after the leaders' debate took place. I have also narrowed down their focus to UK traffic. It will be interesting to look back in a few days time to see whether the initial trends stand up in the longer term.)

The obvious starting point is a direct comparison of the three leaders' names over the past month. Here we immediately see the stark impact of the leaders' debate. Up to and beyond the debate, Cameron and Brown shared a similar level of search traffic, with the Tory leader holding a slight advantage.

It's also telling that search interest in Clegg continued to rise on the day after the debate while his opponents' share dropped away. Clegg's relative anonymity before the event obviously plays its part here - people are more likely to search for clarification when they feel they need it - but it doesn't detract from the fact that a significant number of people chose to actively seek out information about the Liberal Democrat leader and presumably came away more informed.

Just as Clegg himself is keen not to get carried away with this sudden boost in interest, it's worth placing the trend in a wider context. Compared to one of the biggest and most sudden search spikes of the year, the recent eruption of the volcano in Iceland, Clegg's burst is dwarfed but still registers.

Accurately measuring the increase in search volume for the three parties is a far more imprecise affair because of the range of possible terms (Conservatives, Conservative party, Liberal Democrats, Lib Dems) and their common wider use (particularly conservative and labour). As a result, this graph needs to be looked at with a critical eye. There is no doubting the bump Clegg's performance had on associated searches for "Liberal Democrats", however.

A final, tangential note: interest in Clegg over the past year compared to Vince Cable may surprise you. The media line that the shadow chancellor eclipses the party leader in the public consciousness is slightly undermined by this graph which shows a slight but consistent lead in search volume for Clegg. The one exception comes with the shadow chancellors' debate, after which Cable's name received a boost in search traffic.

I agreed with much of Roy Greenslade's recent take on the real value of the internet in this election campaign. But in a three-way competition and with the Lib Dems reliant on the youth vote to create a genuine upset, the internet may play a more crucial role than we assumed.