Should Christians Take Part in Politics?

Some pastors are of the opinion that as religious leaders they should only talk in terms of religions and do not care about politics. I think this is very wrong because we are all part of the larger community of all kinds of people and we are all being subject to all the rules and constitution of the nation. Although you may say you don't care for politics but the politics will control you in many ways and in fact we are being forced to follow all the rules etc. So when the rulers are biased and unjust we have to go against them and we must not keep silent otherwise we would be seen to be part of the greedy regime.  We have seen how an archbishop helped to topple the corrupt Marcos, we have seen other religious people have been joining the multitude to bring down many corrupt rulers in the Arab and Middle East countries so I see no reason why religious men can't take part in the just struggle to cleanse the nation of the sinful and corrupt leaders who have been sucking the blood of the country.