Congress lost power in many Indian States since 2014. It even conceded defeat in Goa and Manipur despite emerging as the single largest party. Neither the National Party showed desperation to form government any of these states nor worried about the BJP having the last laugh.
Whereas, Congress Leadership seems to be now desperate to retain power in Karnataka. This is why the National Party has been in touch with JD (S) since three days and Sonia Gandhi herself came into action after BJP failed to get magic figure. She didn't even hesitate to offer CM Post to HD Kumaraswamy for sharing the power collectively.
Why Congress badly wants power in Karnataka? Just because, This is one state which is so crucial for it to mobilize funds for 2019 Elections. Usually, National Parties divert funds from states where it holds power to the other states at the time of elections. Being in power in Karnataka could give a certain assurance on financial stability for Congress.