Bharti Airtel is mounting a comeback and investors are lovin’ it

Months after billionaire Mukesh Ambani’s upstart Indian wireless carrier swept into the No. 1 spot, a trounced rival is mounting a comeback, and investors are loving it.

Bharti Airtel Ltd. is the best performer on India’s stocks benchmark this year, jumping 26% and reaching a record on May 19, amid optimism the carrier will continue to attract bigger-spending users. The stock surged Thursday in Mumbai after Reuters reported Amazon.com Inc. was in early talks to buy a stake of at least $2 billion.

The comeback is a sharp turnaround for billionaire Sunil Mittal after grueling competition with Ambani’s Reliance Jio Infocomm Ltd. knocked Airtel off its perch in the world’s second-biggest wireless market by users. Mittal’s company reported a record loss last fiscal year, while a shock court order to pay $3 billion in back fees forced the operator to raise capital. Another rival — Vodafone Idea Ltd. — is struggling to survive under a pile of debt.