The latest ammunition for the Congress is the bypoll defeats suffered by the BJP in Phulpur and Gorakhpur, a Lok Sabha seat represented by Yogi Adityanath five times.
"BJP has suffered humiliating loss in the Lok Sabha seats held by the CM & Dy CM of UP. Congratulations to SP & BSP for this historic victory. Unity among the non-BJP parties has played a key role. Perhaps Yogi Adityanath should spend less time lecturing Karnataka on development," tweeted Chief Minister Siddaramaiah who has exchanged barbs with the UP Chief Minister before on Twitter.
The state Congress took a jibe at BS Yeddyurappa, the BJP's chief ministerial face in Karnataka, with another stinging post. "Mr Yeddyurappa, at-least now, show some self respect, and stop bowing to an outsider who can't even win his own seat!"
The Twitter war between the two chief ministers began in January when Yogi Adityanath, in an election rally in Bengaluru, took on Mr Siddaramaiah over issues relating to governance, farm suicides and cow protection.
"There is a lot you can learn from us Sir. When you are here please visit a Indira Canteen and a ration shop. It will help you address the starvation deaths sometimes reported from your state," Mr Siddaramaiah had tweeted.
On Thursday, Karnataka Home Minister Ramalinga Reddy called Yogi Adityanath an "unstarred" campaigner.
But the state BJP insists that the bypoll defeats in UP will have no bearing on Yogi Adityanath's campaign in Karnataka.
"This is by-election. Various factors are responsible for the loss and certainly the party will introspect. He is a chief minister, he is a leader whom people come to see, the bypolls don't change that. For any political party, their star campaigners are widely used during election. Yogi Adityanath will campaign in Karnataka," BJP spokesperson S Prakash told NDTV.
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