The return to the spotlight of paid parental leave invites consideration of a subject that clearly looms large in the Prime Minister’s electoral calculations: namely the gender gap.

First, some historical perspective. Until post-war social currents began to exert their pull on voting behaviour in the 1960s, men were markedly more inclined than women to vote Labor. This was in part because men formed the bulk of Labor’s natural constituency, namely wage-earning members of trade unions. Another factor was the greater role played by church life in women’s political socialisation — which, by the reckoning of La Trobe University politics professor Judith Brett, made conservative parties “the natural home of the morally concerned woman voter”.

But as the participation of women in the workforce grew and the influence of organised religion declined, so vanished the gender gap. Survey data shows that the Labor vote in 1967 was 9% higher among men than women, but this steadily diminished to zero at three successive elections from 2001 to 2007.

That’s not to say that distinctions in men’s and women’s reactions to leaders and political events disappeared, as two telling exceptions to the rule demonstrate. The first was the prime ministership of Paul Keating, whose acerbic style pushed many women to the Coalition in 1993 and 1996. The second was the 2010 election, which was the first and so far only time either major party has been led by a woman. It was also the first election for which the Australian Election Study survey series found women to be more likely than men to vote Labor — and by no small amount: the seven-point differential being the biggest gender gap recorded since the 1970s.

Considering the two exceptions together, the question emerges as to how much 2010 reflected Labor being led by a woman, and how much the Coalition leader being at least a match for Keating in terms of aggressiveness. Gillard and Abbott’s respective personal ratings as prime minister suggest an even balance between the two factors, with the 12.2% gender gap in Newspoll’s average net approval for Gillard being all but matched by a 10.7% gap for Abbott. Such polarisation puts into the shade anything experienced under John Howard and Kevin Rudd, who were respectively rated 1.2% and 2.8% higher among women than men (although the limited polling conducted in Rudd’s second stint as prime minister had him 3% higher among men, perhaps reflecting displeasure among women at his role in bringing down Gillard).

Countering this proposition are findings from the 2013 Australian Election Study which suggest a reversion to type in Gillard’s absence, albeit with a few qualifications. With respect to the Labor primary vote, the gender gap was back to where it had been in 2001, 2004 and 2007, namely zero. However, the vote recorded for the Coalition was still 2% lower for women than men, and a gender gap for the Greens that had disappeared in 2010 reopened to reach a new high of 3% — no doubt because many left-wing women opted for Labor under Gillard’s leadership and the Greens under Rudd’s.

Even so, the 2013 survey results suggest the Abbott factor’s impact on voting behaviour was weaker than his personal poll ratings might have led us to expect. As usual though, there’s a qualification — the manner of Gillard’s removal may have contributed to a loss of support that cancelled out women’s tendency to view Abbott with distaste, which may be more clearly evident next time around.

This proposition is given added force by a turn in polling since the budget. For the earlier part of the Abbott government’s term in office, the trend of gender breakdowns from Newspoll, Nielsen and Morgan pointed to Labor’s two-party vote being about 4% higher among women than men, perhaps suggesting the gap was slightly understated in the 2013 Australian Election Study survey. After the budget, the gap widened to about 6% — much as it was in 2010, this time without the effect of a female Labor prime minister.

What is often described as Tony Abbott’s “women problem” would thus appear to be real and increasingly serious. So to the extent that the paid parental leave scheme represents a politically effective response, the apparent decision to place it on the backburner may have been ill-timed.