NEW DELHI - Tens of thousands of supporters gathered Saturday to see Arvind Kejriwal sworn in as Delhi chief minister for the second time after his upstart anti-corruption party won one of the biggest election victories the Indian capital has ever seen.
The 46-year-old former civil servant's Aam Aadmi (Common Man) Party (AAP) won all but three of the 70 seats in state elections after pledges to tackle entrenched corruption and lower utility bills won over legions of working-class voters willing to give him another chance.
His first term as chief minister lasted just 49 days and ended in chaos a year ago, sparking accusations he was fleeing the tough job of administration.
Before last Saturday's election he apologised for leaving voters without an elected government for a year, telling the Times of India daily that he and his party had "evolved".
Kejriwal's style remains unconventional, but he appears eager to project a more grown-up image this time around.
Posters thanking voters for their support carried images of him dressed in a shirt and jacket and without the trademark woolly scarf that earned him the nickname "Muffler Man".
He is expected to arrive at Saturday's swearing-in by motorcade, after famously travelling by metro to his first inauguration, and has invited the whole city to attend using radio announcements and social media.
Around 100,000 people are expected to turn out for the open-air ceremony at the Ramlila ground where Kejriwal chose to have his first inauguration, in a break from the tradition of taking the oath in the state assembly.
Ramlila is considered the ground zero of India's anti-corruption movement, where huge rallies were staged four years ago.
Hours before the swearing-in was due to start at midday (0630 GMT) thousands of people had already gathered at the ground, many wearing the white paper hats printed with the words 'common man' in Hindi for which the AAP party is known.
Most pundits had written off Kejriwal, especially after his AAP party won just four seats in last year's general elections.
He initially won plaudits for rejecting the VIP culture of Indian politics, but his administration quickly lost its sheen.
He famously declared himself an anarchist during his brief tenure as chief minister and staged several street protests outside government offices.
Kejriwal is expected to outline his priorities for the new Delhi government after taking the oath - though his speech may be relatively brief as he is reported to be suffering from a sore throat and fever.
He will chair his first cabinet meeting later in the afternoon.
He based his election campaign around pledges to deliver cheaper water and electricity and free Wi-Fi for Delhi's 17 million residents, as well as a promise to counter corruption.
In his first meeting with Prime Minister Narendra Modi he pressed for greater autonomy for Delhi, where the central government retains greater powers than in most states.
Kejriwal quit his comfortable and highly sought-after government job in 2001 and embarked on a career as an anti-corruption campaigner that led to national fame.
He came to prominence as an adviser to elderly social activist Anna Hazare, whose 2011 anti-graft drive galvanised India.
Kejriwal went on to found his own party after the men fell out over strategy, with Hazare wanting the struggle to remain non-partisan.
The taxman-turned-politician is reported to have rejected the top security categorisation - known in India as "Z-list" security and reserved for the most senior leaders - because it would make him inaccessible.
In his victory speech on Tuesday Kejriwal, whose supporters span many classes from domestic servants to teachers to business entrepreneurs, appealed to party workers and leaders not to become "arrogant".
"We have to serve people of Delhi and develop it into a city so that both rich and poor will feel proud of it," he told supporters at the AAP headquarters as they showered him with petals.