Why isn't BNP (british national party) in yet!?

i don't understand how the BNP , WHICH IS CLEARLY THE BEST PARTY TO VOTE FOR! in terms of immigration and the saviour of the British population and also getting Britain back on track! i have read all what the BNP would do and it is clearly the best! so why isn't it getting voted for!! the mess the government is in today is ridiculous!