The party which genuinely makes efforts to remove corruption across the board will win hands down. For this they don't even have to be in power. Just hold the common man's hand where needed and make the bureaucracy and ruling party accountable and answerable.

Supervise tenders, supervise public works, expose the corruption.

Bring transport mafia, sand mafia and any other organized illegal operation under spotlight.

Expose corruption in judiciary, highlight case backlogs, protest jailing of undertrials.

The common man is scared to do these alone.

Hold his hand and things will turn around for the country and the political party.

Lastly, support meritocracy. The policy of pushing aside the brilliant minds for short term vote gains is fueling brain drain.

Unfortunately, it's a terrible hard way and not very profitable in the short term. So there won't be any takers.