(Bloomberg) -- The UK’s opposition Labour Party is on track for a landslide victory at the next general election, according to a new poll — with a higher than typical sample size — that is likely ramp up the pressure on Conservative Prime Minister Rishi Sunak.

Labour could win 470 seats at the election, with the Tories plummeting to just 129, according to the baseline scenario of an MRP poll by Focaldata, which asked 10,140 people in Great Britain how they intend to vote. That would give Labour a huge majority of more than 140 seats, it said.

This is the first so-called MRP poll under new constituency boundaries due to come in at the next election, which must be held by January 2025 at the latest.

Still, Labour’s lead is actually smaller than the last time Focaldata ran an MRP poll, suggesting Sunak has won back some Tory voters following his party’s polling nadir during Liz Truss’s brief premiership.

According to John Curtice, an influential polling analyst who’s also a professor of politics of Strathclyde University, the fact the Tories have few allies in Parliament suggest their only potential route to forming the next government would be to win 315 seats — and the survey shows they are far short of that.

Still, the governing party could yet dent Labour’s ambitions, he said. “If you define winning as denying Labour a majority, that’s still up for grabs.”

The debate over whether Labour, which holds a double-digit lead in most opinion polls, is on course for an outright majority or merely the largest party in Parliament intensified after initial analysis of local election results last month. That showed a strong performance by the opposition party but likely relying on smaller parties to form a government.

But subsequent analysis has made more of the evidence of tactical voting in that poll, which points to a far worse picture for the governing party.

Focaldata’s survey also points to a dire outlook for the Tories. Its Multilevel Regression and Post-stratification aims to give a more detailed prediction than a standard opinion poll, taking local factors into account to predict the result for each seat in Great Britain. Northern Ireland is not covered.

The pollster did consider other possible scenarios that could reduce the chances of a big Labour victory.

If the right-wing Reform party was to stand aside for the Conservatives in their marginal seats, as the Brexit Party did in the 2019 election, Labour would win 401 seats and the Tories 201, the analysis showed.

But even in the worst-case scenario for Labour — in which the considerable bloc of undecided voters also break for the Tories, in addition to Reform standing aside — it would still be the biggest party in a hung Parliament, it found.

(Updates with comment from Curtice in fifth paragraph.)

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