WASHINGTON — Jacob Colker's task was formidable: rapidly assemble a network of campaign volunteers to launch an insurgent candidate to the Democratic nomination for a statewide office in Maryland against a well-organized, two-term incumbent.

His plan was a natural, at least for a 23-year old.

Go to MySpace.com and Facebook.com, the hugely popular social-networking sites, and seek out college students in the region whose profiles showed both a political science major and a liberal viewpoint.

With that, the campaign of Peter Franchot for comptroller had exploited the latest twist in political networking to winning effect, using the click of the mouse over the knock on the door. By pushing the two Web sites most popular with young voters, the campaign recruited 80 percent of its volunteers. Within four weeks, that youthful army made 15,000 phone calls, dropped 50,000 pieces of campaign literature and Franchot won the September primary.

"Right now, that's the best way to reach youth," said Colker, who learned the art of drawing crowds while promoting his rock band, Medici, in his native Chicago.

Social networking is but one of the new technologies political campaigns are enlisting in this year's unusually competitive, bitterly partisan midterm elections. While news coverage of the campaign focuses on war, terrorism, economics and immigration, the parties and candidates are engaged in a furious backroom struggle to one-up the opposition in adapting to the new virtual playing field.

Technology's march injects extra potential for volatility in this year's elections, opening the way for candidates who master the new political art forms to make a breakthrough. With the public so intensely polarized, achieving even slight shifts in support can produce decisive gains on Election Day, particularly in a midterm election that typically is dominated by core partisans.

At the same time, the midterms serve as a technological testing ground for the coming presidential campaign, with the most successful innovations certain to be rolled out on a far grander scale in the richly financed contest for the White House.

Almost every serious campaign has a Web site, often with a robust video component, a regularly updated blog and buttons that users can click to donate or volunteer. Many candidates have created profiles on MySpace or Facebook, and both parties have set up their own social networking sites to link together activists. And campaigns are exploiting YouTube.com for both positive and negative ends.

Democrats claim that Party Builder, accessible through the Democratic National Committee site democrats.org, has already attracted more than 10,000 people since a Sept. 5 launch. MyGOP, available through the Republican National Committee site gop.com, also claims thousands of people, with profiles displaying each activist's progress toward goals for fundraising, volunteer recruitment and voter contacts.

With on-demand video, DVDs and online entertainment eroding television audiences and devices such as TiVo permitting growing numbers of TV viewers to skip commercials, politicians also are searching for new ways to communicate with voters, including viral marketing campaigns spread by individuals through e-mail.

Political gaffes and clever attack ads can now spread quickly over the Internet through video-sharing sites. A few campaigns are experimenting with cell phone text messaging, though primarily to rally existing supporters.

Sophisticated campaigns also are tailoring customized messages to smaller and smaller slices of the electorate. What campaign strategists call "microtargeting" has been made possible by an explosion in privately maintained consumer databases and advances in data-mining techniques also used in the war on terror.

The change has been swift since the now-quaint time in 1996 when Lamar Alexander, then a Republican presidential candidate, called a major press conference to announce that he had a Web site. Broadband access has surged. By August this year, 75 percent of U.S. Internet users had broadband access at home versus 51 percent two years earlier, according to Nielsen/NetRatings.

With broadband, people are spending more time on the Internet. And the Web has become a much more powerful political tool as it has become an easy way to spread audio, photos and, most notably, video.

The anticipated easy glide of Sen. George Allen, R-Va., to a re-election victory came to an abrupt halt in August after he was captured on video calling an Asian-American campaign worker for his Democratic challenger a "macaca," a term considered a racial slur by some. Though also broadcast on the news at the time, the episode took on an extended life on the Internet, with the video clip rapidly spreading throughout the world and persisting as a phenomenon for weeks.

With inexpensive digital video cameras and the ease of video-sharing over the Web, a campaign can effectively track an opponent on its own without depending on the uncertain attention span and editorial judgments of profit-minded mainstream media. As a result, local campaigns increasingly are subject to the kind of constant scrutiny that previously had been reserved primarily for presidential campaigns.