This map shows what would have happened in the 2010 General Election if all the people who didn't vote had actually voted for the same party.
We call this party 'The Apathy Party' and you can see it on this map in black.
The map shows that, in the majority of constituencies, non-voters heavily outnumber those who voted for the winner.
This is particularly acute for Labour, who would have been reduced to just a handful of MPs.
In almost all of London's constituencies, the number of non-voters was much higher than the number of those people who voted for the eventual winner.
Nationally, in 2010, if The Apathy Party had been a real organisation, the results would have been:
Will this happen again this year? Not if everyone goes out and votes!