Modi (63) and Gandhi (43) also represent a generationtional change in their parties. Kejriwal, 45, is the new and spirited challenger, keen to change the established political order.
Modi is the prime ministerial candidate of the Bharatiya Janata Party. Gandhi is leading the campaign of the Congress and Kejriwal is the main campainger of the Aam Aadmi Party.
Modi has embarked on a planned and well-publicisied campaign and is expected to some 185 "Bharat Vijay" rallies before campaigning for the Lok Sabha polls ends next month. Modi has garnered so much media attention that BJP's national campaign effectively centers around him.
Kejriwal is the new challenger, keen to change the established political order.
Congress sources said Rahul Gandhi is expected to address about 80 more rallies over the next month. Congress president Sonia Gandhi is also slated to address rallies across states.
Kejriwal, who is pitted against Modi in Varanasi, has been reaching out to peole through road shows and rallies in different states.
AAP sources said that Kejriwal will focus on Varnasi in the coming days.
Modi likes to engage with the audience during his speeches and laces his remarks with sarcasm. He poses questions and then seeks replies from the gathering. Modi raises local issues to build enthusiasm among people, some of whom resort to sloagneering in his favour.
Unsparing in his attacks, Modi almost ritualistically takes digs at the Nehru-Gandhi family. A natural speaker who appears at ease, Modi delivers his punches hard. He speaks at an easy pace and tries to use expressions that can create headlines.
In his rallies in Haryana and Rajasthan, Modi made jibes at Congress over the alleged land deals of Sonia Gandhi's son-in-law Robert Vadra . He refers to Rahul Gandhi as "shehzada (prince) and to the Congress as the "sultanate (Mughal k"ngdom)".
Modi uses Hindi adages to sharpen his attack and speaks on an array of issues including price rise, defence, women's security and education. Modi has sought to identify himself with the the expectations of aspiring classes and presents himself as a strong alternative to the perceived discontent among people with the Congress-led United Progressive Alliance government on issues of price rise, corruption and "policy paralysis."
Rahul Gandhi's speeches have been increasingly targeted towards Modi, portraying him as a know-all, dictatorial leader with a communal mindset.
Gandhi looks less grim than his BJP rival and delivers his speeches in a less serious and sarcastic tone. He talks about entitlements brought about by the Congress in the last 10 years and seeks to identify the party with the poor, the youth and the middle classes.
Gandhi presents himself as a leader who likes to work by consultation and consensus, who values the opinion of others and wants to sort out problems through the process of accommodation. Gandhi appears keen to look informal, accessible and approachable. In some of his rallies he has dressed in jeans and a kurta - a sartorial combination popular across college and university campuses.
Gandhi's speeches can appear repetitive to those who follow him closely.
In his rallies, Gandhi has targeted Modi over the Gujarat model of development and snoopgate and the BJP over "divisive politics". He has also sought to present Congress as a unifying force whose heart is with the poor and which is keen to expand opportunities for every Indian.
Kejriwal speaks and dresses in the manner of the common man. Normally clad in a shirt and trouser, Kejriwal's delivery style is simple, direct and forthright. He seeks to avoid rhetorical flourishes and speaks like a man who does not want to indulge in the politics of compromise.
Kejriwal does not move with heavy security and associated paraphernalia. Kejriwal speaks with confidence and seeks to link success and failure of his party with that of common man. He gives the impression of a leader detached from the privileges and perks of high office with a keen desire to end the problems of the people.
Battling allegations of being a "quitter" after his AAP government resigned in less than two months of assuming power after the Delhi assembly elections, Kejriwal presents himself as a leader prepared to make any sacrifice for his principles.
His attacks on the Congress and BJP for their alleged cosiness with the corporates and his strong anti-corruption plank appears to have struck a chord with people.
AAP is perhaps the only party in the country which has put up candidates on over 400 Lok Sabha seats in less than two years of its formation and looks poised to achieve status of a national party.
Political analysts said that Modi, Gandhi and Kejriwal were trying to be strident in their own ways.
Senior journalist B. G. Verghese said that people coming for rallies do not necessarily vote for the same party.
"Each of them has his own style. Modi is asking votes for himself and is very strident in his stance and so is Rahul and Kejriwal. They also repeat themselves," Verghese told IANS.
He said BJP has launched a concerted advertisement campaign and questions would be raised about the money involved.
Subrata Mukherjee, a political analyst who taught at Delhi University, said Modi was the most impressive of the three lead"rs as "he has the punch".
"He also answers charges leveled against him. He has developed the Gujarat model and has something to show which others do not. He carefully picks on the weak points of his opponents," Mukherjee told IANS.