It may feel as if the Labour leadership contest is never-ending, but with three candidates now on the ballot, buckle your seatbelts for the final stretch. Judging how “electable” each candidate is will surely be high on every Labour party member’s list, as the movement contemplates five more years of Tory rule.

Back in 2015, there was a lack of curiosity from much of the media about Jeremy Corbyn’s success; it was easier to cry “cult” than investigate why an objectively average candidate could inspire such passion and devotion. Corbyn’s election as leader largely came from two points: his willingness to stand up for the party’s principles, and the intellectual deficit shown by his opponents as they failed to offer any solutions to the problems of the post-financial crash era. In a party that had triangulated itself beyond recognition by abstaining on a welfare bill that would push disabled and working-class people into destitution, a leader willing to stand up for Labour’s traditional values of compassion and solidarity was a lightning bolt for the members.

And yet we now face a fresh task. While Corbyn’s victory came after just five years in opposition, by the next general election, Labour will have been out of office for 14 years. The path to power is also steeper: the party now needs to recover from its worst result since the 1930s. There’s no avoiding that, nor is it inspiring to attempt to. Genuine hope does not emerge from empty words or denial, but comes from acknowledging reality and collectively building a plan to fight back.

Rebecca Long-Bailey – who alarmed many with her perfect score of Corbyn after his landslide defeat – has notably honed her message, giving a keynote speech last week on how to win power, while urging members not to give up on an ambitious policy agenda. Lisa Nandy has been particularly vocal on the scale of the party’s task. Keir Starmer, pitched by his team as the “unity” candidate, has been focused on proving his leftwing credentials. It’s the difficult position candidates in a leadership contest following a mass defeat find themselves in: they must simultaneously show loyalty to their predecessor in order to court members, while displaying an awareness of inescapable truths about Labour’s failings.

Electoral victory is the ultimate prize and evidence suggests that Labour members – deeply unsettled by December’s result – are taking this truth to heart. One YouGov poll found that only 14% of Labour party members wouldn’t compromise their values “at all” in order to gain power.

Electability is said to be a dirty word for parts of the left. This is largely nonsense: in an era of Conservative-driven poverty, broken public services and threats to workers rights, few groups are more desperate to gain power. But electability has become a somewhat loaded term. On the one hand, it has become a description for candidates who are willing to conform to the status quo, while those pushing for societal change are dubbed “unelectable”. To see this in practice, look to the US. where Joe Biden has been cast as the “safe option” while an altogether stronger candidate, Bernie Sanders, is said to be the risk. On the other hand, candidates who profess concern for electability are accused of “selling out”: they’re painted as the suit-wearing yes-man who will pivot from their ethics if it seems electorally pragmatic.

This fear is understandable. Labour has the chipped immigration mugs to remind us. But neither interpretation is quite fair. Indeed, the framing of the YouGov question betrays part of the problem: when we talk of electability, we are working from the assumption that taking office inevitably means a choice between principles and power.

In reality, electability is considerably more complex. Research suggests our interpretation of electability is typically a mix of media influence, self-fulfilling polls and psychological biases based on gender and race. That’s not to say certain politicians aren’t more likely to be popular with voters, or that we can’t make personal judgments when picking the leader of the Labour party. We can look at a candidate’s baggage or personality and calculate if it will be advantageous or insurmountable. We can learn from the voting trends in recent years and infer what characteristics will appeal to former Labour voters We can look at what’s happening in other democracies across the world. But it’s not a science, and it’s ever-fluctuating. As one researcher in the US put it: “We don’t know who is electable until someone is elected.”

Only in questioning the notion of electability can the Labour party come close to being elected. This will not mean watering down policies but offering effective leadership and a coherent message that resonates with lost voters. Above all, it means putting aside assumptions and being open about what to do next.

The tightrope is not an easy one to tread. To simultaneously listen and to lead. To doggedly defend principles while showing humility and taking constructive criticism about what hasn’t worked. To inspire the committed while prioritising the unconverted. But it’s a tightrope any Labour leader hoping to win over both the membership and the electorate will have to master. To be electable twice-over is the real challenge.

• Frances Ryan is a Guardian columnist