TODAY marks 100 days until the EU referendum when voters will decide for or against 'Brexit'.

The battlegrounds have already been drawn, with the net cost, immigration and national sovereignty all keys issues ahead of the vote on June 23.

READ MORE:  Seven things the EU has done for Cumbria

You may already have started to receive leaflets through your door or email spam from both campaign camps, Britain Better in Europe and Vote Leave, but things are set to intensify as the weeks go by.

The campaign across Cumbria is heating up, with local supporters and opponents of the European Union clashing on whether an exit would benefit or damage the county's economy, agricultural industry and tourism.

Recent research by YouGov suggests Cumbria is the tenth most eurosceptic area in Britain, with the study suggesting criticism and opposition to EU institutions has a stronghold in many rural communities.

Should Britain stay in the European Union?


Tim Farron, MP for Westmorland and Lonsdale, supports continued membership of the EU. Photo: Ben Birchall/PA Wire Tim Farron, MP for Westmorland and Lonsdale and Liberal Democrat leader, outlined his position on Brexit at the party's spring conference on Sunday (13/03).

Mr Farron said: "We believe Britain thrives when we lead amongst our neighbours in Europe, and will be diminished when we walk away from of the most important group of nations on the planet.

"We can be sure that the UK has no chance of exercising any kind of leadership if it opts for isolation and irrelevance."
Mayor of London Boris Johnson delivers a speech during a Vote Leave campaign event at the Europa Worldwide freight company in Dartford, Kent. Friday March 11 2016. Photo: Stefan Rousseau/PA Wire

Fellow south Cumbria MPs, John Woodcock and Jamie Reed, have also said they will be campaigning to stay in the European Union.

Major south Cumbria employers and business leaders signed a letter published in The Times , outlining their support of continued EU membership.

Sir Roger Carr, the chairman of BAE Systems, Sir Andrew Witty, chief executive of GSK, and Juergen Maier, chief executive of Siemens, all signed the letter, which raised fears over the possible loss of trade with Brexit.

But there are strong voices of discontent, and the coming months of debate could way shift public opinion.

The UK's net contribution towards the European Union comes to £8.5bn each year and critics argue it is money better spent elsewhere, on the NHS for example.

Philip Griffiths, Ukip North West president, said: "If you value freedom and democracy and believe in our country, do not believe anything that Cameron and company tell you, our future should not be in the corrupt EU which is fast becoming yet another dictatorship.

"His so called deal is nothing less than window dressing, there are no reforms and the pathetic changes that he has hailed as a victory can be rejected by the EU institutions at any time in the future."

European Union
Here are 10 facts you might not have known about the EU.
Members
There are 28 EU members, with Croatia the latest to join in 2013.
Budget
In 2015 the UK government paid £13bn to the EU budget, and EU spending on the UK was £4.5bn. This means the UK's net contribution to the EU is £8.5bn.
Spending
Plans for spending the EU budget from 2014-20 include €325bn on support for poorer regions, €278bn on agriculture and €125bn on research and training.
Institutions
There are four key EU institutions:

- The European Commission operates as a cabinet government, with each member state represented. The role of the Commission is to propose legislation and manage the day-to-day business. The Commission is based in Brussels.

- The European Parliament consists of 751 elected MEPs from across the EU who vote on all the laws proposed by the Commission. The Parliament sits in Brussels and Strasbourg. 

-The Council of the European Union is where the governments of each member state can have their say and discuss the political direction of the EU. The Council sits in Brussels.

- The European Court of Justice interprets EU law and makes sure directives are followed in the same way in all EU member states. It also settles legal disputes between national governments and EU institutions and is based in Luxembourg.
Population
An estimated 508 million people live in the European Union and the largest country by population is Germany with 80 million. The smallest country by population is Malta.
Trade
In 2015, British exports of goods and services to the European Union were worth an estimated £229bn.
Referendum
The last vote on the UK's membership took place in 1975 when 67 per cent voted in favour of staying.

A winning deal?
Prime minister David Cameron agreed a package of changes to the UK's membership which would be implemented if the vote to stay wins. These changes include:

- 'Red card' - The red card policy makes it easier for governments to collectively block EU legislation. If 55 per cent of EU parliaments object to a new law then it will be reconsidered.

- Eurozone - Any British money used to bail out eurozone will be reimbursed.

- Sovereignty - An agreement will be drawn up to prevent the Uk being part of an "ever closer union".

- Child benefits - Payments to migrant workers for children living in other EU countries will reflect the cost of living in their home countries. This policy will largely mean eastern European rates will fall.

- 'Emergency brake' - Limitations on in-work benefits for EU migrants can be made during the first fours.
Jobs
It is estimated that roughly 3.5m jobs in the UK are associated with EU membership, however that does not mean all these jobs are dependent on membership. This is one of the key battlegrounds ahead of the upcoming referendum.
Immigration
Around three million people living in Britain were born in other EU countries - which equates to five per cent of the whole population.