Below is the short speech I made on Friday to the Vote for a Final Say rally in London, which saw John Major, Tony Blair and Michael Heseltine share a platform to warn of the dangers for the country if Boris Johnson gets the big majority many seem to predict as the outcome of Thursday’s election. And below that pollster Peter Kellner’s analysis of fifty seats where tactical voting could have a radical impact 0n the result.

It will be quite something if we knowingly elect as Prime Minister someone we know to be a liar – indeed he won the referendum in large part by lying, and his main slogan for this election – Get Brexit Done – is likewise founded on a lie, that somehow Brexit is all done and dusted if he gets his deal through. The sense of betrayal and mistrust will only grow as this pantomime continues.

It is a very dangerous moment for the country when one of the key guardrails of our democracy – a commitment to truthful debate, and a fear that lying will be punished – is taken away. Johnson is doing so as an act of strategy, just as Donald Trump has done. It will change our politics fundamentally, and nobody can say we have not been warned.

As Labour candidates around the country are finding, however, the problem is exacerbated when people do not see the obvious compelling alternative as Prime Minister. Though there remains some enthusiasm for Jeremy Corbyn among his core support, candidates are almost uniformly reporting a negativity about him far greater than that of 2017. As one North East MP put it, for every complaint about Brexit not being done, there are four or five about Corbyn. That Labour are even contemplating defeat in seats historically as safe as they get underlines the real danger that Johnson can win big. We have seen what he is like with a little power. With a lot, he becomes a total menace.

But it is this which means tactical voting – now the only way to stop him – can hopefully take off in a way it might not if people genuinely felt Corbyn was storming to Number 10. In addition to those I mention below, look at some of the seats mentioned in the papers this morning – Dewsbury, West Bromwich West, Bedford and Kempston, Alyn and Deeside, Colne Valley, where the numbers required to lend their vote to help the leading anti-Tory candidate win are in three figures.

Iain Duncan-Smith is just two percent ahead of Labour in Chingford and Woodford Green. If a few Lib Dems and Greens hold their noses and vote Labour, he can be gone. If Labour voters in Winchester lend their vote to the Lib Dems, the Tory can be beaten there. And in Putney, Labour just need a few more Lib Dem and Green switchers to ensure Justine Greening is followed by a progressive, not the hard Brexit Tory who has replaced her as candidate since she was deemed far too reasonable and moderate for Johnson’s Tory Party.

There are lots of tactical voting sites out there, but the one I am looking at most is which sets out the recommendations of all of the main sites. Put in your constituency, and see what it recommends as the best way to stop a Tory. This is not an ideal way to conduct an election, but as I said on Friday, these are far from being ideal times.

Friday’s speech

First of all on behalf of everyone involved in the People’s Vote campaign these last three years I want to apologise — for the fact that as the election was called, due to circumstances beyond the control of anyone involved here today, the fastest growing, and one of the best political campaigns I have ever worked with, was taken off the pitch. You who have marched for it, donated to it and still fight for it deserved so much better than to be so damaged by people supposedly on the same side.

But the fact we are here today shows we have all learned the first rule of campaigning. You never ever give up.

You never give up especially when so much is at stake. And what an awful irony that perhaps the most miserable and joyless election of our lifetime may also be the most important?

In an ideal world, in a healthy democracy, we all just vote for the party and the candidate closest to our views and our values. Sadly, the world is not ideal. Our democracy is not very healthy.

But as we decide what to do in these coming days, how to campaign, how to vote, remember we are not choosing, alas, between Abraham Lincoln and Nelson Mandela. We are not really even choosing between Boris Johnson and Jeremy Corbyn because – if I can let you in on a secret – Jeremy cannot get a majority from where Labour are right now. But Johnson can definitely win. And win big. And if he does that not only are hopes of a People’s Vote severely damaged. But the fears of a massive lurch to the nationalist, populist right become all too real too.

We all want to vote FOR a final say referendum. That means voting AGAINST the party and the prime minister determined we should never get one.

To the man in Wokingham who told me he was voting Labour to kick out the Tories I said no, all that does is keep in John Redwood. Vote Lib Dem.

To the woman in Rossendale who said she hates Corbyn and Johnson so she will vote Lib Dem because they’re ‘harmless’ – no — because vote for them and you are voting for a deeply harmful hard Brexit Tory. Hold your nose. Vote Labour.

To the Labour member in Esher and Walton who said she couldn’t forgive the Lib Dems for the bedroom tax-  ok – but will you forgive yourself if because of your vote Dominic Raab gets back when we have the chance to take him out? Vote Lib Dem.

To the self-confessed Remain fanatic in Wakefield who said she was voting Green to punish Johnson for being Johnson and Corbyn for being – her words – a secret Brexiteer – I said –the consequence is to lose a brilliant remain MP in Mary Creagh and get in one of Johnson’s Brexit robots.

And as I said to a resistant Lib Dem member in very marginal Keighley – my birthplace – if I can vote Labour after being kicked out of the party for voting Lib Dem, you can vote Labour to keep out a Tory who would risk a no deal Brexit at the end of next year. Vote tactically. Campaign tactically. Stop the Brexit landslide.

— Peter Kellner has written a big analysis of tactical voting in today’s Observer. Below a quick and easy guide to how to vote in 50 key seats, and his full piece is here.

Constituency Held by Tactical vote
* Beaconsfield Con Ind Dominic Grieve defending seat he won as a Conservative
Cheadle Con Lib Dem Lib Dems hope to regain seat they held from 2001 to 2015
* Chelsea and Fulham Con Lib Dem City “superwoman” Nicola Horlick standing for  Lib Dems against anti-Brexit Greg Hands in strongly Remain seat
Cheltenham Con Lib Dem Lib Dems hope to gain pro-Remain seat they lost in 2015 to Alex Chalk, a rare pro-People’s Vote Tory
Chingford and Woodford Green Con Lab Big swings to Lab in 2015 and 2017 have turned Iain Duncan Smith’s once-safe seat into a marginal
Chipping Barnett Con Lab Pro-Brexit Teresa Villiers defending 353 majority in seat that voted Remain
* Cities of London & Westminster Con Lib Dem Former Lab MP Chuka Umunna standing as Lib Dem; Tory MP Mark Field stood down after Guildhall fracas
* Esher and Walton Con Lib Dem Dominic Raab at risk in this pro-Remain seat despite defending 23,000 majority
Filton & Bradley Stoke Con Lab Large student population in seat could help Labour overturn 4,000 Con majortiy
* Finchley and Golders Green Con Lib Dem Jewish former Lab MP Lucia Berger standing as Lib Dem in GB’s most Jewish seat
* Guildford Con Lib Dem Lib Dem target also being contested by ex-Tory Anne Milton now standing as Independent
Hazel Grove Con Lib Dem Former Lib Dem seat; 5,500 Con majority would be overturned if Labour supporters (9,000 last time) voted tactically
* Hendon Con Lab Lib Dem challenge has faded in this Con-Lab marginal
* Herts SW Con Ind David Gauke defending seat he won as Conservative
Lewes Con Lib Dem Lib Dems hope to regain seat they held from 1997 to 2015, from Maria Caulfield, who resigned as Con Vice-Chair in protest against May’s Brexit deal
Loughborough Con Lab Local student vote could threaten 4,000 majority; former MP, Nicky Morgan, not standing
* Putney Con Lab Lib Dem challenge has not materialised in this Con-Lab marginal
Richmond Park Con Lib Dem Zac Goldsmith’s 45 vote majority vulnerable to former local Lib Dem MP Sarah Olney
Rushcliffe Con Lab Ken Clarke’s 8,000 majority vulnerable; Con candidate Ruth Edwards pro-Brexit in Remain seat
South Cambridgeshire Con Lib Dem Local former-Con MP Heidi Allen standing down; she now supports local Lib Dem
* Southport Con Lab Three-way marginal that Lib Dems lost to Con in 2017
St Albans Con Lib Dem Strong Remain seat where Lib Dems have built strong local base
St Ives Con Lib Dem Andrew George hopes to regain seat he held from 1997 to 2015
Totnes Con Lib Dem Sarah Wollaston standing as Lib Dem candidate in seat she held for nine years as a Conservative
Truro & Falmouth Con Lab Lab has best chance in area that used to vote Lib Dem
Uxbridge Con Lab Boris Johnson’s 5,000 majority could be vulnerable to large Lab vote by Brunel University students
Wantage Con Lib Dem Ed Vaizey, ex-minister and critic of Johnson, standing down in seat with growing Lib Dem challenge
Watford Con Lab Labour has best chance of retaking the seat, despite Lib Dem challenge
* Wimbledon Con Lib Dem Lib Dems now challenger in strongly Remain seat
Winchester Con Lib Dem Lib Dems hope to regain seat they held from 1997 to 2010
Wokingham Con Lib Dem Arch-Brexiteer John Redwood faces Philip Lee, who switched from Con to Lib Dem, in this Remain seat
Wycombe Con Lab Outside chance of upset in this once-safe Con seat held by ERG leader Steve Baker
York Outer Con Lab Big student population voting tactically could put 8,000 Con majority at risk
* Kensington Lab Lib Dem Former Con MP Sam Gyimah standing as Lib Dem; Lab now third
* Portsmouth South Lab Lab Three-way marginal held by Con, Lab and Lib Dem in recent years
Sheffield Hallam Lab Lib Dem Controversial Lab MP Jaren O’Mara standing down after winning seat from Nick Clegg in 2017
Ynys Mon Lab Lab Three-way marginal between Lab, Con and Plaid Cymru
Aberdeen South Con SNP A Labour seat until 2015, SNP now has best chance of overturning Con majority of almost 5,000
Angus Con SNP SNP needs to squeeze Labour vote to regain one of its former strongholds
Ayr, Carrick and Cumnock Con SNP Three-way contest in 2017, with Labour now in third place
Banff and Buchan Con SNP SNP’s Paul Robertson needs to squeeze both Lab and Lib Dem support to overturn Con majority of almost 4,000
Dumfries and Galloway Con SNP One-time Labour seat won by SNP in 2015 and Con in 2017. Lab now trailing; SNP now had best chance of gaining the seat
East Renfrewshire Con SNP Three-way marginal; Lab until 2015, SNP now established as local challenger to Con
Gordon Con SNP Lib Dems held Gordon for 32 years until 2015, but came fourth in 2017
Moray Con SNP In 2017, Con unseated Angus Robertson, SNP leader in House of Commons; SNP needs to overturn 4,000 majority
Ochil and South Perthshire Con SNP SNP seeking to squeeze Lab vote, almost 11,000 last time, to regain seat they won in 2015
Stirling Con SNP Historically a Con-Lab marginal, SNP now has best chance of overturning Con majority of just 148
East Lothian Lab SNP Three-way marginal last time, SNP has best chance of stopping Con gaining seat it has never won before
Kirkcaldy & Cowdenbeath Lab SNP Gordon Brown’s seat until SNP gained it in 2015 – and lost very narrowly back to Lab in 2017
Midlothian Lab SNP One-time safe Labour seat now a three-way marginal where split anti-Brexit vote could let in the Tories