David Cameron used to always remind people who asked him about what Boris would do in the referendum that the London Mayor had never advocated Britain leaving the European Union. But tonight, Boris will do exactly that. He will become the highest profile politician to back Brexit.
Boris’s decision shakes up this referendum campaign. The IN campaign have long seen a swing to IN among Tory voters as the key to them securing a decisive victory. They believed that Cameron and pretty much all the Tory party endorsing the deal would provide that. But they cautioned that if Boris went the other way, the Cameron effect would be pretty much cancelled out—and that is what has happened.
With Boris and six Cabinet Minister backing Out alongside close to half of the parliamentary party, it is impossible to claim that the Tory party is largely behind this deal. This will have a knock on effect on Tory voters. Another consequence of the fact that Boris and Michael Gove are both backing Out is that businessmen, celebrities and donors will feel free to back leaving the EU without it looking like a UKIP endorsement.
Boris’s decision also shakes up the Tory kaleidoscope. He is now the favourite to be the OUT candidate in a post-Cameron leadership contest. But he has also taken a risk, he is pitting his national popularity against Cameron’s. One IN Cabinet Minister told me yesterday that ‘If Boris joins the Out campaign and gets outgunned, then it’s curtains for him.’ But it is worth noting that most Tory members, who will select the next Prime Minister, will probably back Britain leaving the EU and so will look kindly on those who campaigned for that.
The odds in this referendum still favour IN. But Michael Gove gave OUT intellectual heft and respectability yesterday and today Boris Johnson is giving it popular appeal. This will now be a proper, close fought campaign.
SPECTATOR EVENT: EU REFERENDUM - THE BATTLE AHEAD
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