"How can a labourer like me sit before you?" "What is our level that we can sit with people like the Congress President who look down upon us", he asked.
He called Rahul a "Naamdaar", while saying that he was a "Kaamdaar". "Yes, you are right, you are a "naamdar", what right do we "kaamdaars" have to even sit in front of you".
The BJP is contesting from all the 224 assembly segments in the state in a bid to return to power after it lost to the Congress in the May 2013 elections.
Addressing a rally in Santhemarahalli in Chamarajanagara district, PM Modi attacked the Congress party.
Before Modi addressed the voters, Yeddyurappa, the BJP's chief ministerial candidate, said the BJP will win more than 150 states.
Accusing the Congress government in the state of shielding sand mafias, Modi said those who loot can not be accepted to remain in power.
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Janardhana's brother G Karunakara Reddy is contesting from Harpanahallli on a BJP ticket. Cheif Minister Siddaramaiah is also campaigning extensively to garner support for Congress. "But Deve Gowdaji is among the greatest leaders and I have no right to forget that", he added in Hindi. Last week, the Congress released its manifesto for Karnataka in which it promised to create one crore jobs in next five years. PM Modi further said, "Dynastic Politics not only ruined the party but also ruined the democracy and the country as well". Today, the only word that exists in the people's heart is imaandaar (honest).
The Prime Minister's attack came in the wake of Rahul Gandhi's challenge last week that if he was allowed to speak for 15 minutes in Parliament, Modi would not be able to withstand it.
The Prime Minister also attacked former Congress President Sonia Gandhi and former Prime Minister Manmohan Singh over their promises of providing electricity to every village by 2009.
"I challenge him for an open debate on a single platform on crime and law and order situation in Karnataka viz-a-viz BJP-ruled states".
He also claimed that the Congress could not tolerate the fact that the BJP-led government at the Centre got a majority in the 2014 general elections. Modi had a counter-dare for the Congress president. Congress is spreading lies.
Speaking briefly in Kannada, he exhorted the audience to change the government and bring in the BJP.