From the Guardian UK:
The long-drawn-out fight for the Democratic presidential nomination is likely to benefit the party in the November general election because its campaigns are gathering massive amounts of data on voters, party strategists said.
Information gathered by supporters of Hillary Clinton and Barack Obama during door-to-door canvassing has been passed on to the Democratic National Committee (DNC), which plans to use it in the November election against the Republican presidential nominee, John McCain.
The data, which can be as simple as a correct phone number and address for a likely Democratic voter, will help the party mobilise its turnout operation and raise money for the costly general election fight, according to party strategists.
In Pennsylvania, campaigners for Clinton and Obama as well as the party have registered 328,000 new Democratic voters since last May, and their information has been added to the party’s national voter data file. The Republicans, however, have seen their party registration shrink by more than 73,000 voters during the same period.
(Via – Dan Savage)