By-election results: Why Boris Johnson is no longer a winner and it's either change or lose for Tory MPs

The swing is significant, the victory for the Liberal Democrats overwhelming.

It demonstrates that Boris Johnson is no longer a winning force for the Conservatives.

Even the most optimistic of his supporters would likely concede he required to hold on to the seat in Devon to continue claiming such a talent.

The question MPs will now be asking is if the serial winner – even against all odds – is no longer winning, what does the Prime Minister bring to the Conservative party?

It is hard to argue that he brings a unifying political vision. The closest he has to one is the amorphous, ill-defined concept of ‘levelling-up’.

Brexit also no longer provides an easy political weapon as the cost-of-living crisis overtakes petty disputes with the 'other' of Europe in the list of voter priorities.

Labour, still reeling from the 2008 crash, is now more trusted on the economy.

In a recent documentary on New Labour, former chancellor George Osborne said: "When the economy collapses and you are the people in charge, particularly if you've been in charge for a long time, basically your time is up."

It is hard to see how this does not apply to the situation of rocketing inflation, strikes and struggling post-Brexit trade.

Johnson cannot even claim to be more virtuous than the opposition alternative.

He is a law-breaking Prime Minister who oversaw significant criminality in his own home in the middle of a national and global emergency.

If the cliché the Conservatives are more concerned about power than policy or personality holds any truth, Johnson losing his Midas touch should lead to his rapid defenestration.

One of the successes for the Conservatives has been an ability to reinvent itself in the minds of voters with every new leader.

It is possible a swift change of leader could see a similar recovery.

Failing to do so will likely see Tory MPs ushering in a change of government and their own move to the opposition benches.

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