Many people may vote for Conservative myself included for a number of reasons.
Conservatives are suggesting policies that i quite frankly would love to see implemented, from primaries locally (a idea from Daniel Hannan that Cameron has adopted). More power to Bank of England (a shadow of its former self) in which power has been sucked from by Labour. The lessening of this police state, the fact they opposed ID cards which i absolutely despise. Reform of HOL and consitutional changes has also been proposed. Economically, spending will be hit one way or another. I'd rather it be now than have it be a shock. Rebalancing of power and attitude with our relation with US. (Reviewing the treaty signed by Blair) and if Lisbon treaty is not passed before conservatives get in. A referedum.
Pretty good reasons for me to go blue from where i am standing and run as far as possible from the party which has took us to 2 wars, restricted our civil liberties and use fear to force through bills not to mention has placed UK in debt by their actions.
I trust conservatives and liberal democrats over Labour on every single issue.