Margaret Thatcher once famously said: “The only poll that matters is the general election.”

Over the years, more party leaders have wisely repeated her cautious advice when faced with huge poll leads.

Under latest Labor leadership YouGov MRP Big Poll However, it’s not just big. Huge: Sir Keir Starmer secured a majority of 154 seats.

Not that the Labor leader will pop the champagne corks or dream of moving into 10 Downing Street any time soon.

Despite months of leading by as much as 20% in dual polls, Sir Keir has imposed iron discipline on his inner circle and shadow cabinet members to prevent the dangers of complacency.

But Labour’s top brass will be quietly satisfied as the latest major poll confirms the party’s lead over the Conservatives in opinion polls has not yet declined worryingly.

Indeed, the YouGov MRP poll suggested Labor would gain a larger majority than predicted by the last major poll in mid-January, which predicted 120 seats.

Another change from the mid-January poll is that the number of people surveyed increased from about 14,000 to nearly 19,000, making the sample size really large.

But if Labor is reassured by the findings, the Conservatives will plunge into another round of bloodshed, open civil war and attempts to oust Rishi Sunak.

Well, let’s look at Mr Sunak and the Conservatives’ most optimistic scenario: there are thousands of people who “don’t know”, UK reform has reached its peak and the wavers will return to the Tories.

The big health caveat with the YouGov MRP poll is that it asks voters how they would vote if an election were held tomorrow. Well, not tomorrow, and probably not for more than six months.

Speaking on the campaign trail in northeast England this week, Sunak said he hoped to hold an election when people “feel like things are getting better” and reiterated his plan to go to the polls in the second half of the year.

“I have made it clear many times that my working assumption is that we have a general election in the second half of the year,” he told BBC Radio Newcastle. “That has not changed.”

Labour’s 154-seat majority in the new poll is approaching the 179-seat majority won by Tony Blair in 1979, although well below the 254-seat majority suggested in another MRP-style poll in mid-February. seats.

There is no doubt that many of the new poll’s predictions will be questioned by MPs and party officials, who will be studying its every detail in the coming hours and days.

For example, many in senior Labor circles will argue that predictions of 201 seats for Sir Keir and 403 seats for Sir Keir are too high given that the Conservatives currently hold 53 seats in the House of Commons.

The SNP are sure to question predictions that they will lose 29 seats in Scotland, falling to just 19. There appears to be some optimism that Sir Ed Davey’s Lib Dems won 38 seats to take 49 seats.

However, polls like this will fuel debate among MPs over whether the next election will be like 1992, when Neil Kinnock’s Labor was confident of winning but John Major won by 21 seats , or in 1997, when Blair won by a landslide.

Unlike now, where the government now wins most Commons votes with a majority of around 70 votes, by 1997 Major’s majority had all but disappeared. As Sir Keir often points out, this time “we have a mountain to climb”.

Mrs Thatcher was right to be skeptical of opinion polls. But Sir Keir can take comfort from the fact that this new poll suggests Labor is on the right path as it attempts to climb the mountain.