The ground reality is that Congress cadre has lost the confidence of defeating Congress. Moreover, Congress has no leader of Modi's stature who could Modi's oratory and management skills. Modi, being an organisation from his RSS days, is deft at managing the oraganisation, suppressing rebellion and putting in place a well-oiled booth-management team.
Every government faces the challenge of anti-incumbency and Modi govt,too, has its share of anti-incumbency that includes dissatisfaction in areas that witnessed partial drought but whether that can transform into mass rejection of Modi's policies , is difficult to predict.
In the days of Indira Gandhi, Congress had very meticulously crafted KHAM vote bank but it's no longer working for the Congress as BJP has successfully made inroads into almost all sections of the society including SCs and STs.
The advantage with Modi is that he himself comes from backward community and he has got support of forward communities as well because of two factors.