THE Conservatives are maintaining a sizeable lead in new poll, but four in ten say they may change their minds.

The Ipsos MORI Political Monitor shows the Tories have comfortable lead with 44%, to Labour's 28%, while the Liberal Democrats are on 16%, the Brexit Party on 3% and the Greens on 3%.

Brexit is seen as the top issue helping voters decide which party they’ll vote for with 63% mentioning it, then the NHS (41%), education (21%), taxation and protecting the environment (both 11%), and managing the economy (9%). Brexit is particularly important to Conservative and Liberal Democrat supporters (76% and 77% respectively).

Labour supporters, however, care more about the NHS int he election, with 48% saying it is their biggest issue, compared to 45% saying Brexit.

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The new poll also reveals that while three in five (59%) of voters say they’ve made up their mind on who they’ll vote for – some two in five (40%) say they may change their mind. In May 2017, 32% said they might change their mind.

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Gideon Skinner, head of politics at Ipsos MORI, said: "The public are telling us that they care more about the outcome of this election than previous ones, and yet four in ten say they might change their minds – also more than in 2017.

"At the moment the Conservatives have most reason to be pleased – they keep their lead in voting intentions and their supporters are less likely to say they may change their mind than Labour or the Lib Dems. But there is clearly potential for this to change as the campaign continues."

Those who say they will vote Conservative are more sure of where their 'x' is going than those voting Labour.

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Seven in ten (71%) Conservative backers say they have definitely decided compared with 54% of Labour supporters. More Liberal Democrats supporters say they may change their mind than are definitely decided (by 60% to 40%).

Labour voters who may change their mind are most likely to consider the Liberal Democrats. Meanwhile Liberal Democrat voters who may change their mind are most likely to consider Labour - with around a third of each pick the other party.

Conservatives who may change their mind are split between the Brexit Party, the Liberal Democrats and the Green Party.

And one in five (20%) think a hung parliament would be a good thing for the country while nearly seven in ten (72%) think it would be a bad thing.

Ipsos MORI interviewed a representative sample of 1,228 adults aged 18+ across Great Britain. The interviews were conducted by telephone between November 15 and 19.