British MP Boris Johnson, left,  kisses a wild salmon standing next to with porter Greg Essex at Billingsgate Fish Market in London, Wednesday June 22, 2016 on the final day of campaigning before Thursday's EU Referendum.  (Stefan Rousseau/PA via AP)  UNITED KINGDOM OUT NO SALES NO ARCHIVE
British MP Boris Johnson, left, kisses a wild salmon standing next to with porter Greg Essex at Billingsgate Fish Market in London, Wednesday June 22, 2016 on the final day of campaigning before Thursday's EU Referendum. (Stefan Rousseau/PA via AP) UNITED KINGDOM OUT NO SALES NO ARCHIVE Credit: Stefan Rousseau

Campaigners on both sides of the crucial vote on whether or not Britain should remain in the European Union began the final frantic day of campaigning on Wednesday, crisscrossing the country to make impassioned pleas to the undecided.

Prime Minister David Cameron outlined his vision for a future with Britain retaining its place in the 28-nation bloc, bristling at the notion that the country would be headed in the wrong direction if it stayed in. He flatly rejected the notion that the institution is moribund.

“We are not shackled to a corpse,” Cameron told the BBC. “You can see the European economy’s recovery. It’s the largest single market in the world.”

The most notable figure in the “leave” campaign, former London Mayor Boris Johnson, kicked off a whirlwind tour of England as he pushed for a British exit – or Brexit. Touring the Billingsgate Fish Market, Johnson mugged for the cameras with fish in hand – a not-so-subtle reminder that this is an island nation – and one very proud of its independence and self-assurance.

“It’s time to have a totally new relationship with our friends and partners across the Channel,” Johnson said. “It’s time to speak up for democracy, and hundreds of millions of people around Europe agree with us. It’s time to break away from the failing and dysfunctional EU system.”

Britain goes to the polls today after a campaign that has been both heated and complicated. The reach of the EU into every aspect of life has meant that all sorts of groups – from scientists to CEOs – have registered opinions on whether to stay or go.

The stakes are high as the vote is final – unlike an election in which the results can be reversed in the next term.

Much of the debate has hinged on the economy. From the international banks in the skyscrapers of Canary Wharf to the traditional home of Britain’s financial industry in the City of London, business has largely awaited the referendum with trepidation and caution. Many fear a vote to leave would undermine London’s position as the world’s pre-eminent financial center and damage an industry that underpins the British economy.