Bharatiya Janata Party legislator from the Jayanagar assembly segment, B N Vijaya Kumar, died here early on Friday, a party official said. He was 60.
The two-time lawmaker was in the fray from the same constituency for the May 12 Karnataka Assembly elections.
"Vijaya Kumar was admitted into a nearby hospital after he collapsed on Thursday evening following a cardiac arrest while campaigning in his constituency," the official told IANS.
He died at the state-run hospital after efforts to revive him failed, a doctor said.
The party's state unit chief B.S. Yeddyurappa mourned the death. "I am deeply pained at the untimely demise of my friend and party stalwart Vijaya Kumar...," Yeddyurappa tweeted.
Chief Minister Siddaramaiah also expressed his condolences over Kumar's demise. "..I express my condolences to his family and loved ones. Vijaya Kumar was a sincere and hardworking political leader," he tweeted.
The Election Commission was likely to countermand the poll in Jayanagar Assembly seat on account of Kumar's death as a candidate in the fray.