"Politics is huge on Facebook – we expect it to be the most discussed topic in the U.K. this year," Elizabeth Linder, Facebook's politics and government specialist for Europe, the Middle East and Africa, said in a statement.
Facebook added that its data also revealed that the number of people discussing the SNP, led by Nicola Sturgeon, has increased by 61 percent since April 1 – more than any other party.
Sturgeon became the pro-independence party's leader in 2014 after the SNP failed to persuade Scots to vote for independence from the U.K.
The day after an April 2 seven-way leaders' debate, Sturgeon tweeted that she had gained 15,000 new followers on Twitter, in one sign of her impact on voters in the social media sphere.
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Darren Lilleker, an associate Professor at Bournemouth University, whose research focuses on political communication, told CNBC that the parties were taking social media more "far more seriously" during this election, but that it remained "largely a broadcasting tool."
"They use Facebook and Twitter in similar ways to push out messages rather than communicating with their supporters," he added.