While voting is often unpredictable, it seemed the result of the Crewe and Nantwich by-election was a fairly safe bet. But the scale of the result is incredible. Most incredible is not the swing, but the swing in relation to the turnout. With 57.6% voting, and with votes being similarly apportioned as in 2005, just with the top two reversed, this is not a mid-term aberration. Usually we find low turnout, the incumbent's supporters demobilised, and so a candidate can sneak in through the backdoor only to lose it at the next election. This is not a case of being elected due to your opponent not getting their voters out. Unless the other 42.4% of the constituency are all loyal Labourites who previously voted, and a large proportion of the Conservative voters did not vote previously, then a lot of allegiances have switched. Probably for the first time since 1983, or maybe even before, Conservatives are winning voters from Labour.
The combination of factors caused this landslide, and one that perhaps depressed the Labour vote as well as perhaps providing the final push to potential switchers was the style of the campaign. Despite the Brown 'bribe' as it seems to have been perceived, voters had little reason to vote Labour and every reason to give the Conservatives a chance. Tamsin Dunwoody's campaign did nothing to make the case for Labour instead it was full of eye-catching, negative gimmicks that offered the perception of a desperate, personal-attack, based strategy. Of course this result means that the media will increasingly play up the fact that Labour will lose and Brown should go, perhaps creating at least one self-fulfilling prophecy.