NEW DELHI: The reverses in the by-poll results on Thursday have underlined the challenge that the BJP may face against a likely united opposition in the Lok Sabha elections, but its leaders asserted that national issues combined with the Modi factor will pave the way for its win in 2019.

The BJP's loss in Kairana Lok Sabha and Noorpur assembly by-elections to joint rival candidates following a similar drubbing in Gorakhpur and Pulpur Lok Sabha by-polls has made it abundantly clear that it is at a numerical disadvantage to a combined opposition in a state key to its fortunes in the general elections.

It had won 71 seats and its ally another two of the total 80 seats in the India's politically most crucial state in 2014, but reaching near this feat will require a new round of consolidation of votes in its favour.

BJP president Amit Shah had last week said that his party will work to get 50 per cent vote share in 2019 to quell the challenge from opposition parties if they unite.

The party, however, played down its defeat in the by-polls. It could retain only one of the two Lok Sabha seats in Maharashtra.

Its spokesperson and Rajya Sabha MP G V L Narasimha Rao highlighted how the Modi factor has helped the party win in a spate of assembly elections in states, but in by-polls people are driven by local issues, castes and candidates, knowing well that results will not have any impact on governments in either at the centre or states.

"The BJP has secured unusual and extraordinary mandate in four years of Prime Minister Narendra Modi's rule. While Modi continues to swing election after election by his ever-growing popularity... in by-polls local issues, castes and candidates take precedence over national leadership," he said.

A party leader claimed that opposition parties will end up helping the BJP's cause in 2019 by making it "Modi vs the rest" in the Lok Sabha election.

The BJP is bound to benefit, he said, as it will be in a much better position to leverage national issues and its prime ministerial face to seek a fresh mandate against a "disjointed" opposition fighting without a face or any cohesive agenda.

He said the BJP did well in three Lok Sabha elections in 1996, 1998 and then 1999 when its prime ministerial face Atal Vihari Bajpayee was at the centre of national polity and people, gave the BJP-led NDA bigger mandate in one poll after another to put an end to the "unstable coalition politics".

"We are confident that a ragtag joint opposition having many leaders accused of corruption will not inspire confidence among the people, who will choose Modi over them in 2019," he said.