It’s not as if they weren’t warned. Nobody in the Coalition should have been surprised when news emerged this week that rural leader Fiona Simson was considering a run against disgraced former Nationals leader Barnaby Joyce at the upcoming federal election.

Ms Simson, the chair of peak lobby group the National Farmers’ Federation, is the latest high-profile woman to be associated with a movement that could swell into a wave of independent female candidates running in safe Liberal and National seats.

The unofficial movement of independent women storming conservative seats began at the 2013 federal election. This was when Cathy McGowan snatched the rural Victorian seat of Indi from the Liberal MP, Sophie Mirabella. Up until then, Indi had been held since 1931 by one or another of the conservative parties.

It was a close result, with Ms McGowan prevailing by 431 votes thanks to strong preference flows from Labor and the Greens. Ms McGowan won again in 2016, increasing her margin to 4.6 per cent of the vote.

That election also saw Rebekha Sharkie take the blue-ribbon South Australia seat of Mayo from the Liberals. Ms Sharkie is a member of the Nick Xenophon Team (NXT) and not technically an independent. But with the renaming of NXT to Centre Alliance and the withdrawal of Mr Xenophon from political life, she is increasingly perceived as one.

When Ms Sharkie defeated her former boss, the disgraced Liberal MP Jamie Briggs, with the help of Labor preferences in 2016, she became the first woman and non-Liberal to ever hold the seat.

Ms Sharkie had to compete for the seat again this year, after resigning over dual citizenship problems. After initially being written off, Ms Sharkie not only won the seat, but increased her primary vote by nearly 10 per cent.

Kerryn Phelps is the latest flag-bearer in the movement, obliterating the Liberal Party’s long-term hold on Wentworth following the resignation of former PM Malcolm Turnbull. Reflecting the success of independents in Indi and Mayo, Dr Phelps’ election could be attributed to three major factors.

First, she was a high-profile woman with a centrist philosophy and an agenda that appealed to a broad range voters who are disgruntled, frustrated or unhappy with the status quo. Second, Dr Phelps’ skilled campaign team ran a formidable grassroots campaign.

And thirdly, she was only able to get over the line due to Labor and the Greens running complementary campaigns. Both parties directed their preferences to Dr Phelps, and Labor ran dead to ensure she was in the best position (second place) to benefit from those preferences.

A similar three-prong strategy could deliver in 2019 what the Liberal and National parties have seemingly been incapable of achieving this century – the election of high-quality female candidates in safe Coalition seats around the country.

But instead of sitting on the Coalition benches, these women would sit on the crossbench and may even hold the balance of power at some point (although not after the upcoming election, which is likely to give Labor a healthy winning margin).

Ms Simson could be one of those ‘women of merit’ if she decides to run against Barnaby Joyce in New England. Writer and commentator Jane Caro could be another if she makes a tilt against the former PM Tony Abbott in Warringah. We might even see the current Liberal MP Julia Banks, who holds a marginal seat, run in 2019 as an independent.

It’s no coincidence that this movement of independent candidates responding to voter unhappiness with the status quo is made up of women. It’s also no coincidence that these women sense the emergence of a voter uprising in traditional Coalition electorates.

Female voters in particular are fed up with the hyper-masculine and strictly conservative ethos that continues to pervade the Liberal and National parties, and be perpetuated in the selection of candidates for most safe seats. Given the choice to vote for high-quality, centrist candidates who also happen to be women, many of those female voters will choose the alternative and abandon the Coalition.

This is no secret, given we are reminded of the Coalition’s poor primary vote every time a new opinion poll is published. Yet the Coalition ignores the warning, and does so at its peril.

Just after Ms McGowan snatched Indi from the Liberals in 2013, she remarked in an interview: “You should have seen this coming, guys.”

The ABC’s Barrie Cassidy later noted this “served as a warning to the occupants of safe seats everywhere on both sides of politics”, and that if they didn’t see it coming “another McGowan might be just around the corner”.

That prediction might have been a bit farsighted at the time, but five years later it’s becoming reality.