COMPLEX, hard to call, crucial – Thursday’s local elections in England should have politics watchers on the edge of their seats. Why? Because they represent a major challenge to both Boris Johnson and Keir Starmer.

Council and mayoral elections will both get under way this week.

But unlike in Scotland and Wales, where the entire country votes at once, only certain parts of England will set out ballot boxes.

And those contests will play out at a key time for the Prime Minister as he faces unprecedented sleaze allegations over the financing of the redecoration of his Downing Street flat. Those claims, set to be investigated by the Electoral Commission, follow a raft of cronyism complaints about Covid PPE contracts involving his ministerial team and those close to them.

And the contests come as Keir Starmer attempts to build Labour back up following the debilitating losses suffered under the leadership of Jeremy Corbyn.

Of the 143 councils set to hold elections, 54 are in Labour hands, 47 are Tory-run and 33 have coalitions in charge. Just six are held by the LibDems, and that party’s new leader Ed Davey has an uphill battle to rebuild a councillor base which has been shattered in recent years.

Another three newly-formed councils will also go to the vote, with mayoral elections taking place too in many places, including London where Labour’s Sadiq Khan hopes to retain control against challenge from Tory hopeful Shaun Bailey.

But while the Tories may aim for gains in some regions, they’ll be in defence mode in many more. That’s after 2017 results that’ll be difficult to repeat. Back then, the Conservatives gained Tories gained more than 550 seats as Labour and Ukip votes plummeted. Around 400 of this total came from Labour in a result which also handed the Tories control of nine county and unitary authorities. Tory co-chair Amanda Milling has warned party members of a potential “post-Corbyn bounce” under Starmer, calling the party’s own seat share “incredibly high” in what could be seen as a warning, but could equally be taken as expectation management.

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Local elections are of course very different from national contests, with issues like regional bus routes, library services and even the state of the bins sometimes enough to swing a result. But Essex University has found English voters have their minds on national matters, with Covid-19 the most important issue for almost 60% of people.

That’s according to a survey of 3000 folk and could prove a problem for Johnson, whose approval rating has fallen since the turn of the year while Starmer’s star has been on the rise.

But conversely, an end-of-April poll by YouGov revealed a striking 11-point lead for the PM’s party over Labour, putting them on 44 to 33 despite a period that includes not only cronyism claims involving Health Secretary Matt Hancock and others, but also affair revelations involving US businesswoman Jennifer Arcuri. Starmer has dubbed his rival “Major Sleaze”. But while Tony Blair successfully deployed se claims against Tory leader John Major’s post-Thatcher government, Starmer’s salvos don’t seem to be landing in quite the same way.

That’s despite an ongoing stream of leaks against the PM, including the revelation – backed up by witnesses but denied by Downing Street – that the Covid-surviving Conservative would rather “let the bodies pile high in their thousands” than order a third lockdown.

Then there’s the “cash for curtains” saga. But while that’s said to be shaping opinions in Scotland, it’s apparently not cutting through in some key English areas – including, anecdotally, “red wall” areas, where YouGov says the Tories retain a 19-point lead over Labour with working class voters.

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According to Labour sources, people are talking about Johnson’s conduct on the doorstep. Insiders have expressed doubt that this will be enough to create the same kind of seismic shift as was seen in 2017.

And that’s left Labour, too, braced for bad results in many areas it once called home.

There are a few factors at play – the rollout of the coronavirus vaccine is one, the Chancellor’s magic wallet is another. It’s to fund the PM’s much-publicised “levelling-up” agenda, which is supposed to deliver fortune-changing investment in areas with weaker local economies.

It’s unlikely that the Tories will lose anywhere near enough seats this week to cause Johnson to fear about his position, given the strength of his parliamentary numbers – he’s possibly more to fear from ambitious colleagues than council results.

But Labour will seize on any drop in Tory support and is likely to make big licks of any dents it can make in the Tories’ tally and vote share. Holding the mayoral posts in London and Greater Manchester is of strategic importance.

“The best prospect for Labour”, argues Sky News elections analyst Professor Michael Thrasher, “requires both the Conservatives to implode and Liberal Democrats to struggle, in which case a net gain of over 200 seats becomes possible.”

As for the LibDems themselves, Thrasher says protest voting against the two main parties could gift them a net gain of 50 seats – which could allow Davey, too, to claim he’s winning.