As the campaign closes, there is reasonable agreement among the polls about what are the key issues in the general election.
And it is clear that Labour's lead on most of them has been maintained over the four weeks of intense electioneering.
However, there have been significant changes compared to the 2001 General Election.
Many fewer see Europe as a key issue, while asylum and immigration looms larger.
The biggest controversy rages over how important Iraq is likely to be as an electoral issues.
It appears that "bread and butter" issues are more likely to influence how most people actually cast their vote - although Iraq could affect wavering Labour voters in marginal seats.
During this campaign many polls have presented us with the hierarchy of issues that their respondents identify as the most important in this campaign.
This information is important and interesting to know but what does it tell us about the outcome of the election?
Of itself, very little because what we really need to know is whether an issue is of such importance to people that it could either change their vote, or inspire them to turn out and vote rather than stay at home.
So, it is not much practical use having lists of issues unless we know whether respondents believe one party will be significantly better at dealing with them than other parties on offer at this election.
Health tops the issues that people are concerned about
There are, broadly, two approaches to measuring issues in the polls - asking respondents to volunteer issues entirely themselves (unprompted); and asking them to choose from a list shown or read to them (prompted).
Prompted lists of issues have dominated this campaign simply because they give quicker results.
Both methods are valid but they can generate different messages.
Iraq is the biggest example of this difference.
Health is still the most important issue facing the country, according to nearly all the latest opinion polls which have asked this question - and it has stayed top of the poll throughout the campaign.
There is also agreement that next most important issues are immigration, education and crime - although the order between them often changes.
Then there are two sets of issues whose order often changes depending on the way the question is asked.
When asked in an unprompted question - what is the most important issue facing Britain today? - the intertwined issue of terrorism, defence and Iraq come relatively high up.
The ratings of these (more abstract) issues are also very affected by how much they are in the news.
But the issues of tax and public services, pensions and the economy come higher when voters are asked to select items that matter to them from a hit list, as do issues like childcare and housing.
On Iraq, it is interesting to note how question wording changes the answer.
For example, ICM (on 24-26 April) asked which single issue was most important to their voting decision - and only 3% said Iraq.
But in a MORI poll (between 7-ll April), which asked which of any issues would be "very important", 18% mentioned Iraq.
Another MORI poll, which looked at a subset of Labour voters in 2001 who were now wavering, showed that twice as many defectors to the Liberal Democrats were concerned about Iraq as in the population as a whole.
An NOP/Independent poll on 22-24 April (sample 959) suggested that 49% of people agreed Tony Blair was wrong to take Britain to war with Iraq, while only 12% disagreed and 32% said neither.
And 60% wanted British troops withdrawn by the end of the year, with 16% disagreeing and 19% expressing no opinion.
Which party is best?
However, what can we discover about public attitudes towards which party is best, if any, at dealing with the issues of this campaign?
ICM have tracked the response to the question "which political party is putting forward the best policies on..." six times in recent weeks.
In the most recent (published 24-26 April) of the eight issues listed, Labour had a clear lead on six (health, education, the economy, taxation/public services, the fight against terrorism and Europe), while the Conservatives have a lead on one (asylum and immigration) and are on level pegging on the other ( law and order).
Although ICM reports that importance of the health service has fallen from 27% in March to 21% in their latest poll, issues like the economy and taxation and public services has risen, while asylum and immigration have fallen to being the top issue for only 8%.
And worryingly for the Conservatives, Labour has widened its lead on the two economic issues to a 25% advantage on the economy (Labour 46%, Tories 21%) and to a 10% advantage on taxes and public services (Labour 34%, Tories 24%) despite three Conservative tax cut announcements.
Labour has also reversed the Tory lead on law and order, according to ICM, although here the polls differ.
The Liberal Democrats' strongest issues are the environment, where they lead all the parties, council tax, and Iraq, where they have drawn even with Labour, according to another, internet-based poll by YouGov that was conducted for the Telegraph on 26-28 April.
That internet poll give the Conservatives an 11% lead on law and order, and puts them slightly ahead on tax and pensions.
YouGov has also tracked these issues over four polls.
It shows that the Conservative lead on asylum, crime and terrorism has fallen during the campaign (while pensions is the only issue they have improved their standing).
And this poll gives Labour a lead on a wide range of economic and social issues, including unemployment, interest rates, housing, childcare, and transport.
It should be mentioned that internet polling has put the Conservatives much closer to Labour in share of the vote than the other, telephone or face-to-face polls.
Taking a long-term historical view, there appears to be a clear shift away from economic issues in the mind of the electorate, and a growing concern over first crime, and then immigration.
But it is possible that this is because people are currently content with their economic circumstances - rather than uninterested in the subject.
It is true that since 1997, Labour's lead on economic competence - which first occured after Britain crashed out of the ERM in September 1992 - has increased sharply.
According to MORI, who have asked the question about which issues are most important to Britain since the 1970s, unemployment, inflation, and the trade unions were the biggest issues facing Britain in the l979 General Election which elected Mrs Thatcher.
In 1992, when Mr Major was elected, the top issue was unemployment, followed by the NHS and the economy.
Just before the 1997 election which brought Mr Blair to power, the NHS and education were the top issues, but unemployment was still third, just ahead of crime.
And in the 2001 election, crime became the third most important issue behind health and education. Europe, a key campaign issue for the Conservatives, was fourth
But within two years immigration, which was only mentioned by 17% of the population in 2001, had become an important issue to around a third of voters - a position it has maintained every since, and peaking at 40% in February 2005.
Europe, in contrast had dropped from being an important issue for 24% of the electorate in 2001 to one that only 5% saw fit to mention in 2005.
That may change, of course, if there is a referendum after the election on whether Britain should approve the European constitution.