I have flitted between political parties as my views have changed, as the parties' policies have changed and as the world has changed. New Labour is very different to old Labour, Cameron's Tories are different to Thatcher's Tories and the Liberal Democrats (a fusion of the Liberal Party and the Social Democrats) is markedly different to the Liberal Party of Jo Grimond.
I find it strange that people retain allegiance to one party no matter what changes in policies are made. The 'my party right or wrong' brigade have something missing between the ears, the bit which cuts in the engage brain and think circuit.