TONY Abbott has passed his first test as Liberal leader.

In mid-term polls yesterday the Liberals comfortably retained the two stronghold seats of Bradfield in Sydney and Higgins in Melbourne.

Just days after Mr Abbott was crowned Liberal leader the party faced twin by-elections created by the resignations of former Liberal ministers Peter Costello and Brendan Nelson.

Political pundits had expected the Liberals to take a hit in both seats because of the infighting that has gripped the party over climate change.

But before the evening was over, both Liberal candidates had declared victory.

On a two-candidate-preferred basis, the Liberals' Paul Fletcher led the Greens' Susie Gemmel in Bradfield last night by 63.5 per cent to 36.5, while in Higgins the Liberals' Kelly O'Dwyer leads with 57.6 per cent against the Greens' Clive Hamilton with 42.4 per cent.