The Congress Party is the oldest party in India. Congress was the first party to come to power in India when India became independent 66 years ago. So obviously, all the great personalities in Indian history belong to to the Congress party. India became independent because the leaders of the Congress party who were freedom fighters agreed with the British for partition of India in 1947 into Hindustan(Now India) and Pakistan based on religion(Millions of hindus and muslims died during the migration. That was the beginning of hindu-muslim hatred).
All Hindus were forcibly thrown out of the newly formed Pakistan, who then took refuge in the newly formed India.(They are still called refugees in some parts of northern India). But the newly formed India did not throw out the muslims due to Mahatma Gandhi's principles of non-violence(Gandhi was an advocate of Congress). They were given a choice to stay back if they wanted to. Due to this, the hindus' sentiments got hurt. They felt that just like Pakistan threw out all the hindus, India should also throw out all the muslims. Since the Congress Party did not do so, Congress party earned itself the tag of being a pro-muslim party.
Later taking advantage of this tag, BJP was formed portraying Congress as an anti-national party and themselves as a pro-hindu party to oppose and dethrone the Congress(bloody communal politics). BJP has always been pro-hindu and in its reign, many serious hindu-muslim clashes have happened resulting in death of thousands of both hindus and muslims.(In one such riots, many BJP leaders including Narendra Modi himself were accused for instigating the riots. Later Modi was given a clean chit by the supreme court but other BJP leaders got convicted). The current scenario is that everyone knows that BJP is not secular. It's principles are based on the fundamentalist RSS principles. But there is still a chance that BJP might win, as people are fed up with the Congress which looted India in the last 10 years through highly corrupt practices. But it is sure that muslims who constitute more than 25% of the vote bank will not choose Modi or BJP.
In India, essentially most if not all politicians are illiterate and come from a criminal and rowdy background. There is a Modi wave. If Modi comes to power, there might be development as he promises. But to make him win, we will have to vote for a lot of criminals in every constituency. Just yesterday, I was checking through the data of all the candidates in my constituency. The congress candidate is charged with 2 criminal cases, the BJP candidate was charged with 2 criminal cases, the JDS candidate was charged with 1 criminal case, where as the AAP candidate was a clean person and the most educated and most accomplished.
So with all the goondaism present in Indian politics, AAP comes across as a genuine attempt to clean the political garbage scene. But AAP claiming to be non-corrupt does not have corporate funding. Also, AAP has slightly socialist and Robin Hood views. Within the 7 weeks when it was in power in Delhi, it ordered a probe into some private giant companies(Reliance) as it felt that they were looting the common people in collaboration with Congress Government. So, no corporate wants them in power. So no funds. They are unable to spend like the BJP and Congress in campaigning. Also, AAP being a new party, is not very organised. So internal disputes in the party and lack of vision plague the party, though its intentions are very good.
Public view says Modi will become the PM. He may not win with clean majority. But he will form an alliance Govt. Congress chances are meek due to the corruption and also due to Rahul Gandhi who does not seem to be a promising leader(very unimpressive in his speeches and interviews). AAP has not fielded enough candidates to with the election. They are contesting for the first time. So even if AAP wins all the seats it is contesting, it will still not have a majority. Only the educated and people concerned about corruption, and the aggrieved common man will vote for AAP which might eat into the Congress votes.
Overall, chances are better for BJP and Modi!