New Delhi, April 10 -- Indian Prime Minister Narendra Modi came to power in 2014 promising big-ticket economic reforms. But with unemployment rising and signature policies getting panned, Modi's Bharatiya Janata Party has adopted a nationalist pitch ahead of a general election that begins this week.

The last time the BJP sought a second term was 2004, when it spent millions on an ad blitz projecting India as an economic powerhouse.

The voters didn't buy it. Election results showed that people voted according to their caste, an ancient hierarchy in India that is outlawed by the constitution but still vital in Indian politics.

Hindus comprise about 80% of India's 1.3 billion people, so the BJP is invoking its Hindu nationalist roots, wit...