Indian Prime Minister Narendra Modi addresses his Bharatiya Janata Party's campaign rally in support of East Delhi candidates ahead of Delhi state elections in Delhi, India, Feb. 3, 2020. (Xinhua/Partha Sarkar)

 
Indian Prime Minister Narendra Modi's right-wing party has suffered a crushing defeat in an election for control of the capital New Delhi after a vitriolic campaign in which it concentrated on defending a controversial new nationality law.

Followers of the upstart Aam Aadmi Party danced in the streets and set off fireworks after their leader Arvind Kejriwal, a tax officer turned anti-corruption campaigner, easily won a second term on Tuesday.

The defeat in Delhi is the latest in a string of setbacks for Modi's BJP in regional elections over the past two years.

The AAP, or "common man" party, won 62 of the 70 assembly seats. 

Modi's Bharatiya Janata Party increased its tally from three to eight in the city of 20 million people but was still left licking its wounds after conducting a bruising campaign.

Modi, whose party won a second landslide in national elections last year, congratulated Kejriwal and his party. "Wishing them the very best in fulfilling the aspirations of the people of Delhi," he said on Twitter.

The BJP used the election to rally support for a law easing citizenship rules for religious minorities from Bangladesh, Pakistan and Afghanistan, but excluding Muslims. At least 25 people have been killed in protests over the legislation.

It vowed to end a protest against the law by women blocking a New Delhi highway for the past two months if elected. One BJP deputy minister was banned from the campaign for chanting "shoot the traitors" at a rally. Afterwards, there were three shootings at demonstrations in Delhi.