Elections 2016: What Jeremy Corbyn has to do to survive
"There are two things I am not mentioning on the doorstep at the local elections in my area," a former Labour frontbencher confided to me. "Europe. And Corbyn."
The former because it might motivate otherwise disillusioned or dormant UKIP supporters to go to the polls rather than just wait for the EU referendum in June.
And the latter because the settled view of some in the Parliamentary Labour Party is that Jeremy Corbyn's popularity among Labour's membership is not shared by the party's traditional voters.
So while local candidates will feature prominently on Labour's election literature, in some areas the national leader will not.
Indeed the fear amongst some of Mr Corbyn's own MPs is that he would repel rather than attract support.
So those Corbyn critics who don't want to utter his name are motivated by the desire for Labour to do well in this set of elections.
But privately some in Labour's ranks have been wondering whether to "take the foot off the gas" when it comes to campaigning because a poorer result could convince some of the newer members of the party that Jeremy Corbyn is indeed unelectable in large parts of England, outside London.
This is the school of thought that believes if things are really going to get better for Labour - under a different leader - then first they have to get worse.
But what constitutes worse?
Here the battle of pre and post-election spin won't simply be fought between the parties, but within the Labour Party.
The widespread assumption is that Sadiq Khan will see off Zac Goldsmith in the contest for London Mayor.
He has kept his distance from Jeremy Corbyn - and some of his key backroom staff are exiles from Labour head office who found the new regime un-convivial.
But Mr Khan's victory, if it happens, will be hailed by Mr Corbyn's supporters as an important gain from the Conservatives.
Better still, they will embrace the Conservative attack that Sadiq Khan will be "Corbyn's man in City Hall".
Proof then, they will say, that even an unwelcome association with the Labour leader can help deliver votes, not drive them away.
Corbyn's critics are likely to point out that any win in London should be expected - the party gained seven points in London between the 2010 and 2015 general elections.
And even at the last mayoral election in 2012, Labour gained more votes than any other party in the simultaneous London assembly elections, with 42% of the vote to the Conservatives' 32%.
So the argument goes, Boris Johnson won the mayoralty partly because he is Boris Johnson - but partly because he was up against Jeremy Corbyn's left-wing fellow traveller Ken Livingstone.
At the other end of the UK, the spin will focus on a certain Labour defeat rather than an expected victory.
Polls suggest the SNP will gain another overall majority in the Scottish Parliament.
If Labour finish a poor second under the pro-Trident Kezia Dugdale, Jeremy Corbyn will pretty much escape any personal blame.
Just about everyone across Labour's political spectrum from pale pink to deepest red acknowledges that turning round the party's fortunes in Scotland will take time.
However, in the unlikely but not impossible event that Labour slips to third place in the Holyrood Parliament behind a confident Conservative contingent, the argument will be rather different.
Jeremy Corbyn's internal opponents will bring out the political skean dhus (see above). They will point out that his anti-austerity stance was supposed to win back recent defectors to the SNP.
They will say that while Kezia Dugdale is no Corbynista, she fought a campaign based on tax rises and opposition to public service cuts.
Miliband's good year
If that stance can't improve the party's standing in social democratically-inclined Scotland, what chance does it have south of the border?
And similarly anti-Corbyn voices will be raised if Labour loses its majority on the Welsh Assembly.
But the main battleground will be the English local elections - and the attempt to construct a prism through which the results here are viewed has already begun.
Those close to Jeremy Corbyn are already saying that judging their performance against the 2012 results, when most of these seats were last fought, is unfair - as it was a particularly good year for Ed Miliband, who had had 18 months as Labour leader by then.
Voters had gone to the polls with George Osborne's "omnishambles" Budget - with its pasty tax, its charity tax and the subsequent U-turns on both - fresh in their minds. Labour gained 500 seats in England then.
And the out-and-out opponents of Jeremy Corbyn are already setting this year's bar high - suggesting that at this stage in the electoral cycle Labour should be making more than 400 gains.
Meanwhile, a new analysis by the two leading academics - Colin Rallings and Michael Thrasher - who study council by-election results suggests that, based on Labour's recent performance, the party could be on course to lose 150 seats.
But circulating among some in the Labour leader's shadow ministerial team is an analysis by YouGov's Marcus Roberts - formerly of Labour think tank the Fabian Society.
He has pointed out that - apart from general election years - Labour has only come behind the Conservatives twice in council elections when in opposition in the past four decades.
That was in 1982 - under the shadow of the Falklands conflict and the SDP split - and in 1985, amid the miners' strike and very public battles with the ultra-left Militant Tendency.
Even in Michael Foot's first year as leader the party gained 98 seats.
Mr Roberts says Labour should - by historical standards - be looking to pick up about 300 seats.
The party should be seeking to control councils such as Plymouth, where Labour lost parliamentary seats last year, and Pendle - which Ed Miliband visited on the eve of poll in the general election, but failed to win the next day.
Should Labour fall short of this benchmark, it's perfectly possible that some of Mr Corbyn's own shadow ministers could take to the airwaves and declare that it has - in that classic election programme phrase - been a "bad night for Labour".
Already some MPs who were close to either Gordon Brown or Tony Blair - or both - are weighing up a leadership challenge.
This wouldn't happen until after the June EU referendum, but poor results in the local elections would give them the ammunition.
Jeremy Corbyn's supporters are well aware of the manoeuvrings so apart from being prepared to "spin" bad results, they are organising to achieve rather better ones.
They won't talk openly of target councils but the website of Momentum - the self-declared "successor to the campaign to elect Jeremy Corbyn as leader of the Labour Party" - says it is "organising to support Labour candidates in the various May elections".
Now at one level, it would be odd if they weren't.
But their critics say they are not nearly as committed to campaigning for Britain to stay in the EU.
Some of Momentum's insiders say they will happily focus on that referendum, but only once the local elections are out of the way.
That's because they know good results in May could spike the guns of those who want to challenge Mr Corbyn and make a leadership contest appear bizarre.
And while many on the party's left may feel more motivated when campaigning for Labour candidates who are Momentum supporters, they won't be looking for ideological purity.
The winner of last year's Oldham West and Royton parliamentary by-election, Jim McMahon, is not regarded as particularly left wing but Momentum packed five buses full of supporters from five different cities - about 150 people - to campaign for him, and Labour's share of the vote went up on a turnout of 39%.
Similar targeting of effort in council elections - which also tend to have low turnouts, often in the low 30s - might help make crucial gains or stave off potential losses.
The Labour slogan for the campaign is "standing up, not standing by".
It seems some of the party's MPs will be standing up to - and not standing by - their leader if he and his supporters fail to deliver reasonable results.