The 46% involved in at least one of those activities marks a high point for online political participation, fueled by the twin Web 2.0 trends of Internet video and social networking, according to a new study by the Pew Internet and American Life Project.

"It's very striking to us that already in this campaign we're a level of activity online ahead of what was taking place at the end of the 2004 race," said Lee Rainie, director of the Project. "There are higher levels of intensity among higher levels of people across the board."

The poll found that 35% of Americans have watched online political videos, and 10% have used social networks such as MySpace and Facebook to get information or become politically involved.

That figure jumps to 50% for voters under 30 as young Internet users drive the surge in political activism via social media.

Overall, 40% have gotten news and information about this year's campaign from the Internet, compared to 31% in 2004. Moreover, the share of people getting updates on the presidential race at the end of the primary season has double to 17% from 8% four years ago.

The proportion of African-Americans going online for political news has jumped in particular--to 40% from 19%--while there has been little change among people over 50 and those who are less affluent and less educated.

The Pew study also found that nearly 40% of the population is turning to the Web to access "unfiltered" campaign materials, including video of candidate debates, speeches and announcements, and position papers and speech transcripts.

"In the pre-Internet days, the centerpiece of any campaign was press relations, and candidates depended on mainstream news reporters as gatekeepers," said Rainie. "Now, they have a chance to have their story consumed unfiltered by people who are really into the campaign."

The report emphasized that Americans aren't just using the Internet as a vast reference library, but to take part in the political process. To illustrate, it cites a variety of data: 11% forwarded or posted someone's commentary about the race; 5% posted their own analysis; 6% donated money to a candidate or campaign compared to 2% in 2004.

No candidate in 2008 has benefited more from this upwelling of online activism--or done more to harness it--than Barack Obama. "Simply put, Democrats and Obama backers are more in evidence on the Internet than backers of other candidates or parties," the Pew report states.

Some 65% of Obama's youth-led supporters, for example, get campaign news from the Web, compared to 56% for John McCain backers.

Among voters, Democrats are also outpacing Republicans in their level of political activity online from social networking to contributing money or signing up for campaign-related e-mail. More than one-third (36%) of Democrats have created social network profiles, compared to 28% of Independents and 21% of Republicans.

The study also highlights the impact of the Internet on the 2008 election cycle in ways that are not as easily measured. In particular, it points to campaign stories that gained "powerful urgency" through the viral effect of social media.

Among these, were Obama's comments about small-town voters being "bitter" over job losses and clinging to "guns or religion" reported by Huffington Post blogger Mayhill Fowler, as well as video of inflammatory statements made by Obama's preacher Jeremiah Wright.

After first being posted online by ABC News on March 13, video excerpts of Wright's sermons were viewed millions of times on YouTube, further igniting the controversy and eventually leading to Obama's repudiation of his pastor.

Similarly, McCain was forced to break with preacher John Hagee after liberal blogger Bruce Wilson posted an audio tape of Hagee describing Hitler as a "divine agent" sent to chase Jews from Europe.

"In this season, just the 12th year of presidential politics online, there is no disputing the fact that the Internet has moved from the periphery to the center of national politics," states the Pew report.

Even so, it finds that people still have ambivalent feelings about Internet's role in politics. While the Web has encouraged participation, 60% of Internet users think the Internet is full of misinformation that many voters believe is accurate. And 35% say the medium benefits those with the loudest voices while drowning out the views of average people.

"The most intense Internet users also tend to be the most partisan," noted Rainie.

Not surprisingly, young wired Americans were more likely to express a favorable view of the Internet, with 38% of those ages 18 to 29 saying it helps them feel more connected to their candidate or other cause. Only 21% of those 50 to 64 felt the same way.

The Pew findings were based on a poll of 2,251 U.S. adults between April 8 and May 11.

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