Two damaging by-election defeats in Tory heartlands have piled pressure on the Prime Minister, while Labour will consider its victories further evidence that it is a government in waiting.
Here the PA news agency examines the implications of the by-election results for the political parties and what the outcomes may tell us about the forthcoming general election.
– What were the results of the by-elections?
These were striking by-election wins for Labour and took the Conservatives’ tally of defeats into double figures since the 2019 general election.
In Kingswood the Opposition overturned a majority of 11,220 with a swing of 16.4 percentage points.
This is lower than some of the huge swings Labour enjoyed in previous by-elections, but was comfortably above the 11.4 percentage points it needed to secure the seat.
However, Labour took the Northamptonshire seat of Wellingborough with a huge swing of 28.5 percentage points: the second biggest swing from Tory to Labour at a by-election since the Second World War.
The Conservatives’ share of the vote fell dramatically from 62% at the 2019 general election to just 25%, the largest drop recorded by the Tories at any by-election since 1945.
– What does this mean for the Conservatives?
Many Conservative MPs will have been expecting defeats given national polling but this does not make the losses, and the nature of the defeats, any less painful.
Rishi Sunak delivered a familiar line when he insisted “mid-term elections are always difficult” and said the circumstances surrounding the Wellingborough and Kingswood by-elections were “particularly challenging”.
The problem for the Prime Minister is that the details of the defeats suggest the party is not making progress with voters under his leadership, with no signs his policy decisions and political strategy will be able to shift the negative public perceptions of the party reflected in polls.
The big vote swing in Wellingborough is likely to be a main focus of discussions between Tory MPs and, with recent signs of a potential return of factional infighting, the losses could turn simmering internal unease into something more visible and damaging for the Prime Minister.
Elements of the party, however small, who would like a change of leadership could be emboldened by the results, while others seeking influence after the general election could choose to cause disruption now.
Most of the parliamentary party, even those with reservations about the Prime Minister, will probably accept stability is paramount ahead of a general election but, as prolonged periods of recent turmoil in the party have shown, others could be tempted to rock the boat.
In the meantime, the by-elections will focus minds on the forthcoming Budget as potentially the final opportunity for the Government to shift the narrative ahead of a general election.
But there is also the possibility that, with many households still feeling the impact of a prolonged cost-of-living crisis, a move to cut taxes for example will be perceived as pointless if other costs continue to be high or rising.
There would also be serious implications of tax cuts for future public spending, with frontline services, a key priority for voters, facing a further squeeze in the future.
– What are the implications for Labour?
There will be elation and an element of relief in Labour circles at the results of the by-elections.
But there will also be plenty of internal warnings against complacency which some commentators have suggested crept in after a protracted period of positive polls.
It would be easy to say the victories show Labour’s recent troubles over comments made by two now-suspended parliamentary candidates have not influenced voters.
However, the recent timing of these developments could mean minds had already been made up on voting intentions.
The return of concerns over antisemitism in the Labour Party, at a time when related incidents are rising, could still have an impact – particularly in more diverse areas than Kingswood and Wellingborough.
This is also true of Labour’s stance on Gaza, which is set to be tested again next week by a vote being sought by the SNP on an immediate ceasefire.
Negatives aside, these results will boost confidence and strengthen belief within the party that it is a government in waiting.
This not only has a residual impact on public perceptions but can also ensure MPs and the party machinery remain energised and united in the pursuit of power.
– What are the implications for other parties?
The Liberal Democrats, often the Tories’ main threat in shire by-elections, received a smaller share of the vote than Reform UK, formerly known as the Brexit Party.
The Green Party will take heart in a 3.4% swing in Kingswood, which is its fifth best performance in a by-election.
The bigger picture is that despite increased awareness and concern about the environment, the party’s polling has remained flat around the 7% mark.
Looking ahead, the party’s figurehead and only MP Caroline Lucas is stepping down at the general election, meaning her Brighton seat could be vulnerable to a Labour gain.
Reform UK will be delighted that national polling of about 10% was matched by voting in Kingswood and surpassed in Wellingborough.
The Nigel Farage-associated party poses problems for both main parties.
There is a possibility that Reform UK candidates will evoke memories of the Brexit vote in former Red Wall constituencies and pull some potential Labour support away.
But it is the Conservatives who are most concerned about the party’s impact, reflected in the Prime Minister’s insistence that a vote for the party is a vote for Labour.
There is the simple dynamic of Reform UK splitting the right-wing vote, enticing those tempted by what is perceived to be a more radical, hardline approach to issues such as migration and law and order.
However, evidence from the by-elections may suggest the threat posed by Reform could be exaggerated. For example, even if the Tories had all Reform’s votes in Wellingborough they would still have lost.
But the fact that Reform UK’s vote share in Kingswood was larger than the gap between Labour and the Conservatives suggests otherwise and ensures Tory strategists will be desperate to find ways to counteract the new party’s influence.
– What do the by-election results mean for the timing of the general election?
The guessing game over the timing of the general election continues and the by-elections do not make this any easier.
It is tempting to say the poor Tory performance makes it more likely the Prime Minister and his team will wait as long as possible to give themselves time to turn things around.
This is reinforced by the fact that only one of Mr Sunak’s five pledges, halving inflation, can be said to have been delivered.
Entering a fiercely fought general election campaign in which your opponents can constantly refer to broken promises immediately places the Prime Minister in a vulnerable position.
However, there may be a case for going early if the forthcoming Budget is seen as key, or perhaps the only hope, for Tory prospects at the polls.
The party leadership may seek to immediately exploit an expected bounce in popularity caused by popular measures to boost household finances.
December is still perceived by many as the wrong kind of party season to be holding a general election and a spring election remains fraught with risk.
Autumn, perhaps with progress on more of the Prime Minister’s pledges and some good news on the economy, still looks the most likely date.
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