If a general election was called tomorrow Labour – once an election winning machine - would lose. A result similar to the one that Gordon Brown achieved in 2010 is very unlikely. The collapse of its broad base of support is the biggest problem the party is facing. Tony Blair was good at winning elections, but he had a booming economy and faced weak opposition leaders. Labour cannot repeat the strategy of the 1990s in the 2010s; they need to engage with why they have lost their electoral coalition if the party is to win an election in the future.

The Labour Party typically wins general elections when it has the support of 3 groups: industrial workers (or people living in former industrial areas); metropolitan liberals (Guardian readers); and aspirational centrists (people who think that a Labour government is in their best interests). In 2015 UKIP ate into Labour's support in the first group, the Greens took some of the second, and the Tories took a huge bite out of the third. Despite once dominating these groups, today the prospect of uniting this coalition is distant.

The Labour Party does have some support, mainly amongst middle class, metropolitan, liberals. Many of these are long standing Labour voters, who support Labour because they are the main left wing party. Others are voters who defected to the Greens or Lib Dems and have now been won back by Jeremy Corbyn. These are all voters who are happy with the leftward movement of Labour.

Many of these Labour supporters are people who are put off by politics in general, but are now inspired by Corbyn. Voters who complained that New Labour and the Tories were too similar and like Corbyn because he is different to most politicians. The problem is there are not enough of these people - even if they formed a progressive alliance - to unseat the Tories from power in Westminster.

The collapse of Labour's broad base of support is in part because Labour has become a party of middle class, metropolitan, liberals. Support amongst this demographic has increased under Corbyn, but they do not hold the balance of power in important swing seats like Nuneaton. For Labour to win a general election they need to appeal to a wider group of people. Unfortunately, as support amongst middle class, metropolitan liberals increases, support amongst aspirational centrist voters is decreasing.

The lack of support from centrist aspirational voters is a key reason why Labour lost the 2010 and 2015 general elections. These people blame Labour for the recession and for the stagnant economy that we are still experiencing. They were convinced by Tory rhetoric about balancing the budget and Labour's over spending. Unlike metropolitan liberals, this demographic tends to be less engaged with politics, so the personality of leaders is important to them. Crucially they did not like Ed Miliband and they do not like Corbyn. This is a large voting block that Labour has lost.

The loss of this demographic did not occur under Corbyn. It mainly happened under Miliband's leadership - although Corbyn is not winning them back. Miliband had policies aimed at aspirational centrists - who tend to be more concerned with what a party can do for them than metropolitan liberals – such as gas price freezes, housing market reform, balanced budgets and controls on immigration. However the message was not particularly well delivered, while the Tories’ simple message about economic responsibility, backed up with recent memories of a recession that began under Labour, connected with this group. The 2015 defeat was mainly because Labour could not speak to aspirational centrists anymore.

Is the lesson from this that Labour should move to the centre to win power? Labour could try and win back this group by opposing Brexit, or being tougher on benefits. However this would risk alienating industrial workers. Labour cannot win power with only the support of metropolitan liberals and aspirational centrists.

Industrial workers (or those who live in former industrial areas) are the other key group Labour need, and whose support has been bleeding away before Corbyn was chosen as leader. The main explanation is rising immigration in the Blair/Brown years. Miliband tried to address these voters "concerns" but failed to convince - whilst simultaneously driving more metropolitan liberals towards the Greens. These voters are more likely to have supported Brexit and a reduction in immigration is their key demand. They perceived Miliband as weak (easily portrayed as in the pocket of the SNP) and Corbyn as unpatriotic. Labour is losing these voters to UKIP.

These voters have been characterised as the “left behind”. They are the ones who are losing out from globalisation as industrial jobs are moved overseas to be replaced by low paid and insecure work. These voters have been traditionally represented by the Labour Party, but they have seen a marked decline in their living standards since Labour embraced neoliberal globalisation. UKIP has been successful at winning these voters by blaming their economic problems on the EU and immigration.

Miliband was unable to win them back, and Corbyn does not speak to them, but nor does the right of the Labour Party who still refuse to acknowledge the role of the globalisation they encouraged in eroding living standards.

Tristram Hunt has argued that repositioning on immigration and a more patriotic image would win back these voters, but there are risks of the party alienating voters more if they are seen as being insincere in their patriotism. Cynically exploiting the patriotism of industrial workers for electoral gains will feed the fire of anti-politics, much like Miliband’s statements on immigration drove metropolitan liberals to the Greens and industrial workers to UKIP.

To win over the support of industrial workers Labour needs a means of protecting the living standards of those disadvantaged by globalisation without resorting to UKIP’s tactic of putting up walls and trying to keep the rest of the world out. This is the key challenge facing parties of the left worldwide, from Hillary Clinton to François Hollande. No faction of Labour has a convincing answer to this problem and until someone does, Labour will struggle to win back the support of industrial workers without losing the metropolitan liberals or aspirational centrists.

Labour needs to try and win over from these three electoral groups, but they want different things. This is encapsulated in the question of how Labour should respond to the vote to leave the EU. If it embraces Brexit and controls on immigration to win back industrial workers it is likely to alienate metropolitan liberals (who voted remain) and a significant number of aspirational centrists (who want the economy protected and are were generally in favour of the stability of remain). By opposing Brexit or attempting to limit the degree of Brexit, Labour risk alienating industrial workers who typically voted to leave.

Brexit is just one issues where the views of the three groups differ. Blair was able win huge majorities, but it was much easier for him 20 years ago when the country was less divided and the economy was in Labour’s favour. I am not sure what platform Labour could stand on - with or without Corbyn - that could win back the support of enough voters. There is clearly no easy option and all run the risk of worsening Labour’s predicament. Labour needs to engage with issue head on if they are ever to win an election again. The first issue they need to engage with the wide negative perception of the Labour Party.

Polling station image taken by Rachel H and used under creative commons.