"Though BJP was set to fare poorly but such a disgusting performance, no one thought of," Vaidya, a former spokesperson of the RSS, told reporters.
"The Yeddyurappa factor has worked against the BJP certainly and his exit from the saffron fold played a key role in BJP's debacle" in the only southern state where the party ruled, he said.
BJP suffered a humiliating defeat in the Karnataka Assembly elections as Congress appeared to be well on its way to wresting power on its own after a gap of seven years.
However, ruling out any impact on the 2014 general elections in the country, Vaidya said five states including Madhya Pradesh, Rajasthan and Andhra Pradesh will go to polls later this year which will set the trend for the Lok Sabha polls.
On Gujarat Chief Minister Narendra Modi campaigning in select locations in Karnataka, Vaidya downplayed it saying campaigning by one or two persons makes no impact.
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