The head of India's largest Tamil party has been cleared of corruption, in a verdict received enthusiastically by supporters and paved the way for the return of one of the country's most powerful regional leaders.

A court in southern city of Bengaluru on Monday overturned a lower court's decision to jail Jayalalithaa Jayaram to four years for amassing illegal wealth of at least $10m in a case that ran for nearly two decades.

High Court judge CR Kumaraswamy declared Jayalalithaa's "appeal upheld" at a hearing in the IT hub which lasted only minutes.

"I am immensely satisfied with the verdict... Verdict paved way for me to emerge like tested pure gold," Jayalalithaa was quoted as saying by NDTV news channel.

She was forced to stand down as chief minister of the southern Tamil Nadu after being found guilty last September of amassing illegal wealth while in office.

Although she had been forced to quit as chief minister of the southern state, her return is now seen as a formality as she continued to control her party, All India Anna Dravida Munnetra Kazhagam [AIADMK], while on bail awaiting the outcome of the appeal.

The 67-year-old is hugely popular in Tamil Nadu where fans know her simply as "Amma" (mother) and ministers have been known to prostrate themselves before her.

Dhanya Rajendran, a journalist based in Bengaluru, told Al Jazeera that the acquittal is a move "that will completely resurrect her political career".

"This is a political revival for her like never before ... what a lot of people are asking now is if she would want to come back as chief minister immediately, or if she'd like snap polls, given that Tamil Nadu will have elections this year."

This case has widely been seen as a litmus test of the strength of India's judiciary to follow through and deliver justice in cases involving high profile figures. 

Al Jazeera's Nidhi Dutt said that Jayalalithaa's acquittal will raise questions, "particularly in opposition quarters, about the integrity of the legal system and the will and commitment on part of the courts to actually prosecute those found guilty of corruption".

Devoted supporters

Security was tight outside the court in Bengaluru and in Chennai, the capital of Tamil Nadu, where supporters cheered, handed out sweets and set off fire crackers.

Outside Jayalalithaa's house in Chennai, hundreds of supporters held up photos of their leader and danced in the streets chanting their support.

Party loyalists had been holding religious ceremonies in temples, praying for her conviction to be overturned.

Jayalalithaa has always dismissed the corruption charge, first brought by a rival politician in the state in 1996, as politically motivated.

She was charged in 1997, when police seized assets including 28kg of gold, 750 pairs of shoes and more than 10,000 saris in a raid on her home.

Prosecutors said her assets, which reportedly included two 1,000-acre estates in the lush tropical state she ran, were vastly disproportionate to her earnings during her first term as chief minister, which ran from 1991 to 1996.

Jayalalithaa has earned the loyalty of many voters in Tamil Nadu with a series of highly populist schemes including an "Amma canteen" that provides lunch for just three rupees (five cents), although she has also drawn accusations of an autocratic governing style.

Source: Al Jazeera and agencies