The costly process of becoming an election candidate

The process of becoming an MP is long and expensive - involving not one, but two campaigns.

The one familiar to most people is where a party's candidate tries to persuade constituents to put a cross next to their name on the ballot paper at a general election.

But before that, anyone who wants to be an MP must battle others from their own party to get selected for that seat.

This process in itself can be arduous.

In the Conservatives and the Lib Dems, you must go through an assessment process in order to make it on to a centrally approved list.

"It was a challenge," confessed Paul Scully, recently approved as the prospective parliamentary candidate for Sutton and Cheam.

"I went through the central process a few times before I was successful and I think that's a testament to the process itself because it challenges you and it can say, 'No, you're not ready for it yet, go and get some more experience', so when you do finally get there, on the whole, the list of people are good, tried-and-tested people."

Another Conservative, Owen Meredith, who stood for a Welsh Assembly seat in 2011, agreed: "It takes a long time, from initially putting yourself forward, to the assessment day, to finding out if you're approved, to being assigned a seat. It's quite a drawn-out process. You have to have an understanding employer."

Layla Moran, standing for the Lib Dems in the Oxford West and Abingdon seat in 2015, described the approval process as "surprisingly difficult".

"It's all very professionalised, there's a competency framework, but I knew it wasn't a pass-fail test. The competency framework is useful - it will tell you what your strengths are. I believe I'm good at expressing my party's values, so that's my strength."

In the Lib Dems, if you make it on to the list of centrally approved candidates, you can put yourself forward for any seat.

In the Conservatives, some who do particularly well at the assessment centre are cleared to apply for any seat. Others will be cleared to put themselves forward for specific seats.

After deciding on a seat, hopefuls must then campaign for the votes of local party members. This will usually involve contacting every single party member in a constituency.

Following hustings, in which potential candidates face questions from party members, the local party elects its preferred representative.

If you're hoping to make it big in Labour, you do not have to attend an assessment centre, but until recently it was expected that the backing of a trade union would improve your chances.

The Labour rule book explains you have to be a member of a trade union to stand as a Labour candidate, but you do not need to be endorsed by a union for the final selection.

Labour's selection process has been under the spotlight after Unite, one of the party's biggest donors, was accused of signing up its members to Labour in Falkirk - some without their knowledge - in an effort to get its preferred candidate selected to fight the next election. The union denies any wrongdoing.

In response, Labour leader Ed Miliband has said he wants the relationship between his party and trade unions to change. One proposal is that union members would have to actively opt in to join Labour, rather than being automatically affiliated as part of union membership.

Labour candidate in Norwich North Jessica Asato - speaking before the Falkirk claims emerged - defended unions' role, saying they "are an incredibly important part of the process... they represent thousands of working people".

All three candidates agreed that putting yourself forward for selection can be a financial test, but there was no consensus on how to reform the way potential parliamentary candidates are funded.

Some party activists believe the cost of becoming a candidate favours people with personal wealth to draw on. Research by Iain Dale in 2006 put the cost of being a candidate at around £41,000.

"I had to take a salary drop, go part-time and freelance," said Ms Asato. "It's tough supporting two homes and travel, and tight control of my diary without an MP's salary."

Mr Scully had a similar warning: "A lot of candidates can be quite out of pocket, because of the travelling, the effect that it has on your employment - and not least of all the raffle tickets you have to buy at all the events!"

"I initially thought I couldn't do it at all because I was a teacher," Ms Moran admitted.

"You have to be resourceful. I knew it was going to be expensive, so I had to build up savings and get a second job (with an organisation offering revision courses)."

Naomi Smith, a Lib Dem who contested the safe Conservative seat of Cities of London and Westminster in 2010, argued that it is even more difficult for those representing smaller parties.

"Labour has the support of the trade unions and the Conservatives tend to get more corporate donations, meaning the Lib Dems - sadly - often end up selecting candidates who are personally wealthy," she observed.

"If you want to make it a truly level playing field you'd have to consider some sort of state funding, and that would never fly with voters."

Paul Scully echoed her doubts: "When you talk about state funding you're on tricky territory - I just don't think taxpayers would swallow politicians being paid any more."

Candidates on all sides were more open to the idea of expanding public duty leave, a provision which allows employees a certain amount of days' absence to pursue civic activities, such as becoming a school governor.

Aside from the financial cost, putting yourself forward for selection can also be a drain on your time and resilience.

Paul Scully said that even though he'd been involved in politics for years he found it taxing: "The two years of my life from now until the general election in 2015 are going to be very intense. It's a question of balancing campaigning and family life and keeping a job."

Jessica Asato pointed out that she'd previously worked as an adviser to Labour MP Tessa Jowell, saying it helped to have an employer who understood the demands involved.

"It's been helpful to have support of my boss, she understands. But others will struggle to get that kind of support from their employers," Ms Asato explained.

"The biggest complaint about politics is we don't have enough representative candidates and a big factor in that is most people cannot take extended periods of leave from their job - we need to address that in order to invest in democracy."

But another Labour candidate, who is also a mum-of-three, insisted the tough schedule was necessary: "The process is a taste of what's to come.

"It might be a baptism of fire but that's a good thing. You are thrown in there, and if you are dedicated you can make it work. You need to be determined and definitely need a thick skin, just as you would in Parliament."

Several parties run schemes aimed at encouraging a range of people to put themselves forward. In Labour, there is training and support through the Future Candidates scheme. The Lib Dems have the Access to Elected Office initiative, aimed at helping disabled people get elected.

A group of Conservative MPs including Jeremy Lefroy are looking at the idea of establishing a bursary for candidates.

The question of how candidates are chosen and funded will continue to dominate debates at Westminster as parties reach for the right response to events in Falkirk.

Ed Miliband has called for a clampdown on MPs with second jobs, and the prime minister has said he would like to see a system whereby union members opt in to Labour put into law.

The idea of holding more open primaries - where candidates are not pre-approved by the party - is gaining traction. It has been championed by Conservative MP Sarah Wollaston (herself elected in an open primary) and shadow justice secretary Sadiq Khan, among others.

With the passage of the Fixed-Terms Parliament Act, one thing is certain: the UK will next go to the polls in 2015. But for most of the names on the ballot paper, the battle begins now, under closer scrutiny than ever.