The divide between supporters of independence and unionism in Scotland is providing the Conservative Party with an electoral boost but some warn it could fan the flames of religious rivalry.

On June 8, the U.K. wide general election takes place wit

h a Conservative win predicted in most polls, but it is the party’s resurgence in Scotland that has taken many by surprise.

Robin McAlpine, the director of the left-of-center think tank Common Weal, said the Scottish Conservative Party leader, Ruth Davidson, has successfully cultivated a unionist vote that appeals to many Scots of a Protestant faith.

But he added that the strategy could be risky.

“Sectarianism is a beast that you think you might be able to tame. But you can’t.

“My guess is Ruth Davidson doesn’t know what sectarianism looks like and Scotland won’t thank whoever brings this back,” he said in a call to CNBC.

McAlpine said the Conservative Party in Scotland had reframed the debate as not being left versus right but about whether Scotland should be independent and they had “very successfully” become the biggest unionist vote.

The West of Scotland, in particular, has long wrestled with a sectarian divide between Catholic and Protestant religious faith.

McAlpine said encouraging Protestants who typically support union with England to vote based on their religious persuasion, could bring back violence associated with the past.