Both parties are optimistic, whatever the polls say. Are they right to be?

Welcome to the topsy-turvy election. The mood at the top of both the Conservative and Labour parties is the opposite of what we might expect.

The Tories are cautiously optimistic the opinion polls point to an overall majority for Boris Johnson, but they are haunted by their own complacency at the 2017 election. “My fingers are still burning,” quipped one Tory candidate and former minister.

Similarly, Labour’s and Jeremy Corbyn’s poll ratings are poor, and yet the party is surprisingly optimistic, because it did much better than it expected two years ago. Labour was so convinced the Tories would win an overall majority that it had barely discussed what to do in the event of the hung parliament that materialised.

If Labour closed a 20-point poll gap to just two points during the campaign then, why not now?

“It’s very possible,” insisted one upbeat Labour frontbencher. The consumer-friendly announcement on broadband has put a spring in the step of the party’s ground troops. The partial renationalisation of BT will be controversial, but Ed Miliband’s plan for energy price controls was also attacked as too interventionist by the Tories, who later copied it. The problem for Labour today is that voters who doubt its economic competence might judge free broadband as too good to be true.

“The manifesto was a game-changer last time and it can happen again,” said one Corbyn ally, looking ahead to next week’s publication. In public, Labour must express confidence about winning a majority. But insiders whisper that the party does not need big gains to form a minority government in a hung parliament, since Corbyn would have more potential partners in the SNP, Plaid Cymru, the Greens and even the Liberal Democrats than a rather lonely Johnson would.

Such optimism may prove misplaced: there is no law that says this election will be a re-run of 2017. Some Corbyn-sceptic Labour candidates fear the leader will struggle to repeat his success, no longer being the fresh face voters saw two years ago.

Just as Theresa May was (too) determined to be “not Cameron” on succeeding him as prime minister, team Boris is desperate to avoid May’s mistakes in 2017. She had a longer, seven-week campaign; this time, the Tories plan to delay their manifesto launch, perhaps until just two weeks before the election, in the week after Labour’s.

It’s a safe bet that Johnson’s prospectus will be slimmer and more cautious than May’s; she achieved the rare feat of abandoning her manifesto pledge on social care before polling day.

True, many voters do not focus on the election race until the last lap, or bother to read manifestos. But the documents influence media coverage and can matter, as Labour showed in 2017. There’s an advantage in rolling out policies before the manifesto launch so they don’t compete with each other on the day, as Labour’s broadband announcement shows.

With hindsight, Labour should have already rushed out its manifesto by now. The Tories are cynically attacking their deliberately misleading version of Labour’s policies – notably on tax and spending – before Corbyn’s official blueprint is even published. Not surprisingly, it’s straight out of the 2016 Vote Leave handbook.

Team Boris doesn’t mind at all that Labour disputes its claim that “the cost of Corbyn” will be £1.2 trillion over five years or £2,400-a-year in extra tax for every taxpayer. Like the bogus 2016 claim of a £350m-a-week bonus for the NHS, Boris allies are more than happy to have a row about Labour’s spending plans because it amplifies their central message.

Above all, the Tories want to avoid the complacency of May’s disastrous campaign. Even on election day, Tory advisers thought she was heading for a majority of between 50 and 60. Johnson does not want to look as if he is expecting a big majority. The official line is that he needs just nine more seats for a working majority that would ensure he “gets Brexit done”.

Of course, it suits the Tories to argue the race is close: in 2017, some voters thought it safe to vote for Corbyn because they judged he had no chance of becoming prime minister.

However, the best-laid campaign plans can still leave any party at the mercy of unexpected events. In 2017, terrorist attacks in Manchester and London enabled Corbyn to turn the spotlight towards police cuts and austerity. The floods and the looming NHS winter crisis revealed by this week’s worrying official figures might just have the same effect this time, highlighting the lack of investment during nine years of Tory rule.

Whatever the polls say, the Tories genuinely have no room for complacency. This weekend, those ministers who privately warned Johnson against a winter election will worry that their worst fears might come true. One wonders whether Johnson has repeated one of May’s mistakes: calling an election when he didn’t need to.