Facebook has launched an effort to engage people in the election
Social networking website Facebook is to help get unregistered voters to register before the 20 April deadline.
In a tie-up with the Electoral Commission, Facebook users who visit the site over the weekend will be asked if they have registered to vote.
If they say "No" they will be sent to a page linked to the Electoral Commission that lets them enter details online.
They then have to print out this page and post it to their local council's electoral registration office.
The address for this is automatically created on the page once someone has entered their own location details.
The Electoral Commission says applications have to be sent by post, and not simply via e-mail, because of a legal requirement to prevent electoral fraud.
The Electoral Commission estimates 3.5 million people who were eligible to vote in England and Wales in 2001 were not registered.
Turnout has fallen in recent general elections
A change in the law following the 2005 general election means that the registration period has now been extended until 11 working days before polling day, which this time around is on 6 May.
In 2005 the rules meant that voter lists, based on the electoral roll, were closed by the time the election was actually called.
Electoral Commission spokesman Clinton Proud said the Facebook exercise was part of the organisation's remit to expand access to the democratic process.
"If you're not registered, you can't vote - it's very simple. By downloading and printing a form through Facebook, users can now make sure that they are able to have their say on election day," he said.
"Many people assume they are automatically on the electoral register if they pay council tax or if they have voted before. This is not the case. And if you have moved house, even within the same borough, you need to re-register with your new address."
Richard Allan, director of policy at Facebook, said many of the site's users were traditionally excluded from politics.
"One of the strengths we have is to try and capture that group, particularly the 18-24 year-old voters, who have often not turned out to vote, and use the fact that many of the things on Facebook are familiar to them to get them engaged."
Potential voters can also find out how to register online by visiting the Electoral Commission's registration website, www.aboutmyvote.co.uk.