Immediately after the expenses scandal it was often casually assumed that turnout would plummet at the next election. Since then, two developments have made this prediction unsafe.
First, an election that was widely expected to result in a Conservative landslide has become the closest since 1992. Second, the first ever leaders' debates have taken place and dramatically increased support for the Liberal Democrats, particularly among young and undecided voters.
Perhaps the most important reason for the low turnout in 2001 (59.4 per cent) and 2005 (61.3 per cent) was simply that it was always clear which party would win. There was little incentive for voters, particularly those in safe Labour seats, to head to the polling booths. But this time, with a range of possible outcomes, this is no longer the case.
In 2001 the psephologist Anthony King wrote: "Just provide the voters with a closely fought election at which a great deal is at stake and, make no mistake, they will again turn out in their droves."
There are now several signs that he will be proved right. Half a million people downloaded electoral registration forms in the weeks before the deadline and, we learn today, sales of party manifestos are up 160 per cent on 2005. Unsurprisingly, sales of the Lib Dem manifesto have risen dramatically, up 250 per cent since the last election, while sales of the Tory manifesto are up 193 per cent.
Sales of the Labour manifesto currently stand at 97 per cent, compared to the last election, largely due to a print run of just 2,500.
I doubt that turnout will reach the 71.2 per cent we saw in 1997 but a modest improvement now looks likely.