An opaque third-party activist group with links to Labor and the Coalition will launch an advertising blitz of teal battleground seats in the final days of the election campaign in a bid to win former Liberal voters back to the party.

Paid for by anti-teal, anti-Greens group Better Australia, the ads are aimed at former Liberals who voted independent in 2022 and are worried about peer perceptions of being seen to switch back on May 3.