THIRUVANANTHAPURAM: Congress Working Committee leader A K Antony exuded confidence in Youth Congress state president Rahul Mamkoottathil increasing the victory margin in the Palakkad by-election. Antony also said that the vote share of the BJP will come down in the constituency which has been seeing them make great strides in pushing the CPM to the third place in the last two elections. The veteran leader was speaking to reporters after Rahul called on him to seek his blessings.