Mr Kejriwal said, "This is not my victory but that of the aam aadmi (common man). The common man is the chief minister, not me."
The oath-taking ceremony will be held at Ramlila grounds, which had been a key venue for the anti-corruption campaign that catapulted Mr Kejriwal to national fame. (read: Mango man Kejriwal) Mr Kejriwal said the date of the swearing in has not been finalised yet.
AAP spokesperson Manish Sisodia said there was no ambiguity on who would be chief minister, as Mr Kejriwal had been projected as the party's candidate for the top post. (Legislators will decide on Chief Minister: Kejriwal)
Mr Sisodia is among the front-runners for a cabinet post in the AAP government. Among others being talked about as possible ministers are Vinod Kumar Binny of Lakshminagar and Rakhi Birla of Mangolpuri.
A confident Mr Kejriwal has said the Aam Aadmi Party will fulfill all its election promises, most of which have been criticised as extravagant and unimplementable by seasoned political rivals like the Congress and the BJP.
AAP made a stunning debut in the Delhi elections, winning 28 of the 70 seats in the new Assembly, second only to the BJP but eight short of a majority. The Congress' eight legislators have extended external support to the government.
The Congress' Sheila Dikshit, who was denied a fourth term as chief minister by Mr Kejriwal in the recent Delhi election, made it clear that her party's support was "not unconditional." She said this morning, "Our support is dependent on their performance. I hope he can fulfill his promises. We were aware that it is impossible to fulfill those promises."
AAP had last week asked people to advice it on whether to form government in Delhi with support from the Congress. "74% of the people have favoured that party should form the government," said AAP leader Manish Sisodia. (People want our government in Delhi: Manish Sisodia)
The BJP called the AAP's decision a betrayal. "The AAP accused the Congress of being the most corrupt. Today they have compromised on their principles. This is gross betrayal," said Dr Harsh Vardhan, the BJP's chief ministerial candidate.
Mr Kejriwal's former mentor Anna Hazare said on his alliance with the Congress, "Let them do what they think is good, I don't wish to comment." The two men engineered the massive anti-corruption campaign for the Lokpal Bill in 2011, but fell apart last year over Mr Kejriwal's decision to launch a political party.