It is now law that UK Parliaments must last exactly 5 years. Get out your diaries for the next 50 years and mark the first Thursday in May in 2015, 2020, 2025... to be the day of the General Election. Since we know when the election will be, MPs will be able to schedule their canvassing. It is likely that those MPs who have a small majority will want to canvas for the optimum amount of time before the election to ensure they get re-elected.
Since voters have a short memory it means that once an MP is elected s/he can safely ignore the electorate for the majority of the term as long as they are seen everywhere for roughly a year before the election (and hence voters will not remember that they've been ignored for four years). MPs are paid a salary of about £64k and they do not have to attend Parliament: they do not have to take part in committees nor debates. The only job performance evaluation is on election day, and since elections are more a case of a popularity contest for the candidate (and/or their party leader) their performance in Parliament is largely irrelevant.
Since an MP is the representative of a constituency s/he is expected to do constituency work, but how do you know whether their presence in the constituency is electioneering, or constituency work? This means that an MP can legitimately spend a year canvassing and will be paid to do it.
Love it or loath it, the old system kept MPs on their toes. They did not know when the election would be. Consequently the electioneering occurred during the few weeks between the Prime Minister calling the election and the election day. That is all the time we have to put up with canvassing politician! Under fixed term Parliaments we will have to put up with canvassing politicians for (most likely) eight months. It works like this. The MP will finish a Parliamentary session in July the year before the election and then have a long holiday until September. At that point the public will see politicians on the TV and hence your local MP will have to be seen. For MPs with small majorities this is the time that the electioneering will start.
Rather than spend their time in London, they will spend it in their constituency canvassing (the public pays for them to have a home there). Since they will only need to return to vote in the cases when the vote is tight, that means they will be able to canvas every day until the following May. This gives them 8 months (with one day a week off, that means 200 days). A constituency will be about 18,000 homes. It is easily possible for an MP to visit 18k/200 or 90 houses a day (more likely they will avoid the areas where they are unlikely to get any votes, or areas where they can rely on the vote, which will cut the canvassing down considerably).
All of this means that the incumbent has a huge advantage. They will be paid to canvas and they will have a constituency base paid for. This means they can make sure that they can target swing voters to ensure their re-election.
Other candidates do not have this advantage. If they do not live in the constituency they will have the cost and disruption of buying or renting a home in the constituency. If the candidates is employed they will have to ensure that they work near the constituency (or change job), and they will then have to do their canvassing after a full day's work. This will mean that a candidate will be restricted in the number of homes they could canvas. The only people able to match the canvassing ability of an incumbent MP is someone with an independent income that they can use to finance their campaign. In other words: wealthy people.
The effect of fixed term parliaments is that it will favour the incumbent, and the only people who could challenge a sitting MP is someone who has a pot of cash that they can afford to spend on their campaign. Consequently, the House of Commons will get less representative as the only people able to campaign are the very rich.
Labour have a huge task to gain a majority at the next election. I estimate that Labour would need something like a 12% swing - compare this with the 8.8% swing that Tony Blair got in 1997.
For Refounding Labour I submitted the following idea. The Labour party should select its candidates early, preferably two years before the election (we know when the election will be!) The candidate will then be paid by the Labour party a living wage. say £18,000. The candidate then has the money to secure (rent) accommodation in the constituency and will be able to work full time canvassing. Since this is a wage, it should ensure that people without an independent income will be attracted to stand as a candidate. This should raise the number of women and BAME candidates and make the use of all women lists unnecessary.
A paid candidate will have two years to be seen as being a community leader, getting involved in local issues and hopefully getting results. This raises the profile of Labour in the area (which will hopefully have an effect on local authority elections) and will actually benefit the area. The ultimate result, of course, is that the area will get a Labour MP. If the candidate is elected, they will be an MP with a salary of £64k. This means (and only if they become an MP) they could pay back the money they were paid (say £12k a year, this means the "loan" will be repaid in three years). But there is an important point: they only pay back this money if they become the MP. If the candidate is not successful, they will not have to pay back the money. Since being a candidate should be treated as being a job (performance managed by the local constituency party who will feedback to the central party) the candidate must work as a full time campaigner. Since the candidate knows that they will be paid for the canvassing (and only repay when they become an MP and are earning 3.5 times more) it will not be seen as being a financial drain to be a candidate. The result is that it is more likely that there will be candidates from all walks of life, not just those who have an independent income.
The big issue is if a candidate fails to be elected. I suggest that existing Labour MPs pay for those paid candidates who are not successful. The 240 or so current Labour MPs standing for re-election at the 2015 election will have the advantage of being the incumbent, and so will be a paid canvasser as explained above. This means that there is no need to pay them a candidate's wage. To get a majority of 300 at the next election Labour would need approximately 60 more seats, so it makes sense to target the 100-most marginal constituencies. The money for these 100 candidates would amount to £3.6m and this could be raised by a 7% levy on all the Labour MPs from this point until the 2015 election (assuming MP salary of £64k, 3.5 years to the election). After the next election all MPs could then pay a levy of 4.3% every year (the 60 new MPs would pay this for this after paying off their candidate wage) which would fund 100 waged campaigners for the last two years of the parliament and this could be split between campaigners supporting the 50 Labour MPs with the smallest majority and the 50 target marginal seats.