Exactly two weeks from today, millions of people across the country will be voting in the general election.
Opinion polls continue to suggest the Conservative Party enjoys a comfortable lead over Labour.
The latest poll averages put the Tories on 43 per cent, with Labour on 31 per cent, the Liberal Democrats 14 per cent, the Brexit Party 4 per cent and the Greens 3 per cent.
At this point in the 2017 election campaign, the polls showed the Conservatives on 44 per cent, with Labour on 35 per cent, the Lib Dems on 9 per cent, Ukip on 4 per cent and the Greens on 2 per cent.
But on election day, the Tories finished on 43 per cent – one point below where they had been two weeks earlier – while Labour had risen six points to 41 per cent.
The Lib Dems dropped one point to 8 per cent, while both Ukip and the Greens finished on 2 per cent.
The change was enough to deny the Tories a majority and produce a hung parliament.
There was movement in 2015 as well, albeit on a smaller scale and with different consequences.
Two weeks before polling day in 2015, both the Tories and Labour were averaging 34 per cent with Ukip on 14 per cent, the Lib Dems 8 per cent and the Greens 5 per cent.
These figures pointed to a hung parliament – but come election day, the Tories opened up a seven-point lead over Labour to finish on 38 per cent while Labour ended on 31 per cent.
Ukip, the Lib Dems and Green finished on 13 per cent, 8 per cent and 4 per cent respectively.
This was enough to give the Conservatives a small overall majority in parliament.
The pattern in 2015 and 2017 suggests a lot can change in the two weeks before polling day.
It also serves as a reminder that polls are not predictions, merely snapshots of opinion at a certain point in time.
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