In the Web 2.0 race for the US White House, Senator Barack Obama continues to dominate rival Senator John McCain in several areas.

At the time of the Iowa Democratic caucus in January this year - which Barack Obama went on to win - he led the entire presidential pack in the Web 2.0 world with the most Facebook friends, MySpace friends and YouTube views.

On the Republican side, Ron Paul and Mike Huckabee - the Republican victor in the Iowa caucuses - were the top Web 2.0 candidates with 88,000 and 7,000 supporters respectively on MeetUp, a site that helps supporters organise in-person activities for to rally for candidates.

In the current online race, Obama continues to dominate. On Oct. 21, for example, Obama raked in more than 84 million views for his YouTube videos while JohnMcCain posted 22 million, according to TechPresident, a site that charts Web 2.0 election statistics. Over the past six months, 13,702 Meetup members have used the site to organise offline groups and events to support Obama, while 1,472 members are using it to rally around McCain.

For the seven days ending Oct. 22, Obama was mentioned 10, 291 times in the blogosphere, according to Technorati - which tracks blogs - compared to 3,924 mentions for McCain.

And Hitwise - which tracks web traffic - noted that Obama was pulling in 67% of all web traffic directed to presidential candidate sites while McCain was pulling in 32% of that traffic.

Obama has also continued to dominate on Facebook, with 2 million Facebook supporters on Oct. 9, compared to McCain's 564,000. The Democratic candidate also leads on MySpace, with 749,000 supporters as of yesterday, compared to McCain's 190,000.

Both candidates have leaned heavily on the internet during the run-up to election day with recent moves including Obama's launch of an iPhone application and McCain's move to query users on professional social networking tool LinkedIn and to overhaul his "McCainSpace" MySpace page.

In the days leading up to the Democratic National Convention in August, McCain had a strong online surge - especially in the blogosphere that had long been Obama's stronghold.

Next page: Translating online support into votes

As far as translating online supporters into votes, both candidates have built online tools designed to help volunteers easily identify supporters who can call or canvass voters to help drum up votes, including Obama's "Neighbor to Neighbor" tool and McCain's "Voter to Voter" software.

Micah Sifry, a blogger at TechPresident, noted that it is impossible to know which tool is used more. However, he did note that the Obama tool is more "deeply embedded in the ecology of the Internet."

Sifry also said that a search for the words "Obama" and "neighbor to neighbor" on Google returns 479,000 hits, while a search for "McCain" and "voter to voter" brings back 325 hits. "In both cases, the link to the actual tool is the top hit, which is good, but these search results indicate a great deal more conversation about the Obama tool - and presumably usage," he added.

In addition Sifry's search on Google of the total number of sites linking to Obama's "Neighbor to Neighbor" tool was 475, including 396 blogs. The total number of links to McCain's tool is 18 - with no blogs.

"If you design a tool to be used on a website, more links pointing to it and more web hits on its name generally are signs of greater interest," Sifry went on to note. "Each site pointing back to Obama or McCain's voter engagement tool is a funnel of attention. For some time now, we've been saying that Obama's continuous attention to network-building online was going to give him a huge advantage come the general election."

Still, the Web 2.0 crowd was not always been an accurate predictor of the state-by-state primary contests. Web 2.0 measurements on the day of the New Hampshire primary predicted that Obama would win the Democratic primary and McCain or Huckabee the Republican contest. Senator Hilary Clinton won on the Democratic side, while McCain forged a victory on the Republican side.

Moreover, Julie Barko Germany, director of the Institute for Politics, Democracy & the Internet at George Washington University, said that it is very difficult to draw correlations between the number of Facebook friends or YouTube views with election results.

"We've known all along that Obama supporters tend to be more internet-savvy and tech-savvy," she said. "I don't think we can draw a correlation between that or persuasion or voter turn-out when we pull back and look at the whole country. The most import thing to look at is search engine marketing traffic - who is getting the most searches on Google or Yahoo. It is a really good indicator on who regular voters are searching for."

According to Google's Insight search analysis tool - which shows the number of searches for a particular term compared to the total number of searches on Google normalised on a 100-point scale - "Obama" pulled in 86 searches in the U.S. on the 100-point scale in the past seven days compared to 53 searches for "McCain."

Using the candidates' first and last names, Google Insight noted that "Barack Obama" pulled in 86 searches on the 100-point scale in the past seven days compared with 69 searches for "John McCain."

In related news, Google has launched a new mapping service to help voters to find polling places.