Opposition unity paid off in Uttar Pradesh, with its candidate trouncing her BJP rival in Kairana, the most-watched seat in the by-polls held across 10 states on Monday, The Samajwadi Party also wrested Noorpur from the BJP. Opposition parties have an edge in other states too, leading in one seat where they are pitted against the BJP or its allies and winning five. The BJP retained Maharashtra's Palghar Lok Sabha seat - where it was in contest with estranged ally Shiv Sena - but is trailing in Bhandara-Gondia, which it snatched from the NCP in 2014.