The rise and rise of the unstoppable Theresa May

A Conservative prime minister rolls the dice again. Former prime minister David Cameron gambled twice during his tenure at Downing Street.

The first gamble - the Scottish referendum - paid off. By the second roll - the EU referendum - his luck had run out. Despite Cameron's efforts to renegotiate the UK's EU membership and campaign for Remain, Britain voted for Brexit.

Cameron resigned within a few hours of the result.

Now his successor, Theresa May, has picked up the dice again. By calling a snap general election, May hopes to strengthen her party's grip on the UK's Brexit strategy as she heads into negotiations with the EU.

Sitting prime ministers call early elections only when they are sure they can strengthen their majority.

May has timed the decision well. Conservative support is at a post-2015 election high.

With just seven weeks to prepare for the vote, the surprise announcement caught opposition parties on the back foot.

The Conservatives, meanwhile, can campaign on the back of eight years of unbroken economic growth, a record level of employment, a public sector spending deficit that is falling, and a promise, albeit a vague one, to deliver on Brexit. May's chances of a major election victory look very strong indeed.

The main opposition party, Labour, is badly wounded heading into this election.

Although large numbers of Labour MPs are pro-business, ex-Blairites, the party's current policies are dominated by the far-left persuasions of leader Jeremy Corbyn and shadow chancellor John McDonnell.

Opinion polls show Labour is down some 10 points versus a year ago. Major losses in Scotland in the 2015 general election to the Scottish National Party cannot be recovered this time around, as support for an independent Scotland continues to run above 40%.

Many factors shape elections. But the coming UK general election will be dominated by Brexit.

The latest polls show the Conservatives more than 20 points ahead of the second-placed Labour Party, and 12 points ahead of their support before the 2015 general election. With all other parties at least another 15 points behind Labour, it is almost inconceivable that they could muster enough support within the next seven weeks to win an election outright.

If most Brexit voters side with May, the Conservatives could add around 70 extra seats to their current working majority of 17. But what if the voters don't?

Heeding the lessons of the unexpected outcomes of Brexit and Donald Trump, we need to consider the unlikely scenarios more than before. While the chances of an outright win for any party other than the Conservatives are extremely low, there is some risk of a hung parliament if enough Brexiteers relent, or EU supporters strategically vote against the Conservatives to soften Brexit.

If the June 8 election ends in a hung parliament, all hell would break loose, at first.

The near-term uncertainty could be worse than it was after the Brexit vote. Don't forget, the UK has already triggered the two-year countdown for Brexit divorce negotiations.

A hung parliament would raise the prospect of two wildly different outcomes.

On the one hand, it could leave the UK divided entering negotiations with the EU, raising the risk of an exit without a deal because the UK cannot agree on a strategy in time. On the other hand, if a hung parliament forced cross-party compromise, it could lead to a softer Brexit strategy, and may turn out to be positive in the long run after some serious initial confusion.

But realistically, with just a few weeks to go, the question is not if, but by how much the Conservatives will extend their margin over the opposition. An election win for the Conservatives would strengthen May's influence on Britain's Brexit strategy enormously. But what could it mean?

For the EU27, the UK snap election doesn't matter at all.

Whoever the EU27 negotiates with on the UK side, the EU will prioritise its political interests.

Since Brexit has no major impact on the EU27 economy, the post-Brexit deal will be shaped by the desire to safeguard the cohesion of the EU27.

The EU cannot conclude a deal with Britain that is as advantageous as the terms available to members or potential future members. If Britain accepts the rule of the market, such as free movement of labour, the EU will agree to a comprehensive trade deal.

If Britain refuses such conditions, tough luck.

If May strengthens her own hand in the UK, the negotiations could run a little smoother as she could rely on her - potentially large - majority, and not the support of other parties, to push the final Brexit deal through parliament.

More power over parliament will reveal the prime minister's true colours. More seats for the Conservatives will serve to dilute both the soft and hard Brexiteers in the party while weakening the hand of other more pro-EU opposition parties.

This would free May to pursue the Brexit she really wants. If she is already doing that, nothing much will change.

May is a social conservative, a former home secretary, with no major background in business.

In a sense, she is the least pro-business prime minister since before Margaret Thatcher.

May began her premiership with a speech promising to improve social cohesion in the UK and raise opportunity for the least well-off.

When migration is perceived as the major social issue in Britain today, the chances of May deciding on low restrictions on EU labour to get a good trade deal out of the Brexit talks look slim, to put it mildly.

How will the chips fall if the prime minister's gamble pays off? At best, the election might be a non-event.

At worst, Britain could be heading down a smoother path to a slightly harder Brexit.

Pickering is a senior UK economist at Berenberg Bank