Boris Johnson could fail to win the general election if just a third of Remainers vote tactically

• Boris Johnson will fail to win a majority at the general election if just 30% of Remainers vote tactically, according to research commissioned by anti-Brexit campaigners.
• The election would produce a pro-EU majority in the House of Commons if 30% of Remainers vote tactically, the research suggests
• However, it concluded that Johnson would win a comfortable majority if pro-Remain Brits did not vote tactically.
• The UK will hold another snap general election on December 12.
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Boris Johnson will fail to win a majority in the UK general election if just a third of Remainers vote tactically against the Conservative party, new research published on Wednesday morning suggests.

A survey of 46,000 Brits, commissioned by the anti-Brexit campaign groups Best For Britain and Hope Not Hate, found that the election will result in a pro-Remain majority in the UK parliament if 30% of Remainers vote tactically at the next election.

Under this scenario, Johnson's Conservatives would fall around a dozen seats short of a parliamentary majority.

The Labour Party, which is committed to holding a new referendum, would win 223 seats, while the anti-Brexit Liberal Democrats would win 31, and other Remain parties would win five, creating a Remain majority of four MPs.

If on the other hand 40% of pro-Remain Brits vote tactically, then the Conservatives would be the largest party but with just 277 seats, while Jeremy Corbyn's Labour Party would win 255, creating a pro-Remain House of Commons majority of 36, the research said.

By contrast, the research found that Johnson would win a comfortable majority of 44 if no tactical voting takes place.

The research only applies to England and Wales, as the groups are not the groups are not advising people in Scotland and Northern Ireland to vote tactically.

Here are the main findings:

• Johnson will return a comfortable parliamentary majority of 44 MPs if no tactical voting takes place among Remainers at the December 12 general election.
• The Tories would win 364 seats and Labour would win just 189. The Lib Dems would win 23. This would give Johnson a majority of 44.
• However, if 30% of pro-Remain Brits vote tactically, the Conservatives would be outnumbered by parties which are committed to either holding a new referendum and/or staying in the EU.
• The Tories would win 309 seats, Labour would return 233 seats, Jo Swinson's Lib Dems would win 34 seats, Plaid Crymu would win four, and the Greens would win one. Remain majority = four.
• But the Remain majority would be 36 if 40% of Remainers voted tactically.
• The Conservatives would win 277 seats, Corbyn's Labour would win 255 seats, the Lib Dems would win 44, Plaid Cymru would win four, while the Greens would win one.

Pollsters expect an unpredictable election

Best For Britain and Hope Not Hate want opposition parties to embrace tactical voting at the election.

Johnson's Conservatives are the current favourites to win the election, with polls giving them an average 10-point lead.

However, volatility among the electorate is at a historical high, with huge shifts in voting intention over the past year.

As a result, one polling expert, Chris Curtis from YouGov, told Business Insider this week that there were several reasons to believe that "tactical voting could be more effective" than in previous elections.

There is now "very low partisan alignment" among voters, Curtis said, meaning that the way people voted in the 2016 EU referendum is now a bigger factor in deciding their vote, than which party they backed in the last general election.

According to one recent poll, around a quarter of voters plan to vote tactically in this election.