Ummm, a party WAS formed around that as the main issue. They're the UKIP. In fact, that was their ONLY issue. They didn't win any seats in parliment but they pressured the "major" parties to act on the issue, and the result was Brexit.
The UKIP was formed more than 20 years ago in opposition to the EU. However, the EU then when first formed was merely a customs union which IMO is a good thing. It has now become an extra government that makes laws and has courts that override the sovereignty of it’s members. That did not exist at first. The breaking point in the UK was the unbridled immigration from the middle east rammed through by Germany and Angela Merkel. That is when this movement began and that is of what I speak, a party being formed around that issue or the Tory’s adopting it as part of their platform and standing for election.
The problem was that not enough Torries believed in it and the UKIP was not large enough. Perhaps over time UKIP could have grown to be large enough to have a large say in the formation of the government. This is the problem IMO of the parliamentary form of government. They win elections by plurality, not majority. They then form coalitions around that to govern after the vote. In America we form the coalitions within the two party system before the vote and then win a majority.
As I said previously I don’t like referendums and there are other ways to deal with it. I think if they would have allowed the parliamentary democracy to work, the requisite mandate for this would have happened without the referendum.