Ihave a confession to make. I am a politician. You could be forgiven, after the past six weeks of seeing me fall off a paddleboard, career down a waterslide or plunge from a bungee jump, for thinking that I was auditioning to present a Saturday night light entertainment show. I was, in fact, asking you to vote Liberal Democrat. The “stunts” hopefully show that I do not take myself too seriously. But what I do treat with the utmost importance are the issues that people have raised with me and the stakes at this election, which could not be higher. Elections like this one do not come around very often. This is a once-in-a-generation chance to put an end to years of Conservative chaos that have left families struggling with spiralling mortgages, rents and childcare costs, and our NHS on its knees, while water companies are freely allowed to pump filthy sewage into our rivers and beaches. This election is your chance to give your verdict on the Conservative incompetence that has weakened our economy, ravaged our public services and diminished the UK’s standing in the world. This election is, however, about more than simply the satisfaction of the Conservative party deservedly being shown the door. It’s about winning the real change our country desperately needs if we are to fix the health and care crisis, get our economy back on track and end the appalling sewage scandal. We must transform our politics for good, so that no party can take people for granted the way this Conservative government has. It is tempting to look at the opinion polls and the shambles of a Conservative party election campaign and think that history is assured. But absolutely nothing has been decided yet. There are seats in former Conservative heartlands across the country – such as Bicester and Woodstock, Frome and East Somerset, and Mid Sussex – where seats are on a knife-edge between the Liberal Democrats and the Conservatives. A handful of votes could be the difference between beating the Conservatives and them clinging on. This historic chance for change is dependent on some people voting tactically for the party best placed to beat the Conservatives in their area. In many areas of the country, among them parts of the home counties and the West Country, Labour cannot and will not win. Only the Liberal Democrats are capable of bringing change. In many constituencies – such as Didcot and Wantage, St Neots and Mid Cambridgeshire, and Brecon, Radnor and Cwm Tawe – the only way to beat the Conservatives tomorrow is to vote for the Liberal Democrats. I’m so grateful to the many Labour supporters who have told me as I’ve crisscrossed the country over the past six weeks that they are voting for us at this election because that is the best way to defeat the local Conservative. I’ve been clear since I became Liberal Democrat leader that I see my role as beating as many Conservative MPs as possible. Since then, we’ve focused our resources in the many seats where Liberal Democrats are second placed to the Conservatives. More and more people are focusing on how best to use their vote to bring an end to Conservative rule and start a more progressive, more positive era. But I’m even more encouraged by how many Labour supporters are backing the Liberal Democrats not just tactically but enthusiastically, because of our progressive plans for the country. Our manifesto is full of bold ideas to fix the big challenges we face, such as fixing social care. The big banks and billionaires would be asked to pay a little bit more in tax so we could fund the NHS and care properly. Our natural environment would be improved by banning water companies from dumping raw sewage into our rivers, lakes and coastal areas. Our politics could be transformed for good by introducing a fair voting system that gives MPs in safe seats nowhere to hide. And our broken relationship with Europe must be fixed to boost our economy and international reputation. A vote for the Liberal Democrats in many areas at this election is the best way to defeat the Conservatives, but it is more than that. It is a vote to change our country’s future, to start to build a more progressive politics and a better Britain. Ed Davey is leader of the Liberal Democrats