With Election Day fast approaching, the media blitz is in full force in Northern Virginia--a flurry of TV ads, telephone solicitations, video clips, campaign fliers and World Wide Web postings aimed at turning out the electorate Nov. 2.

The campaigns for state and local offices have been marked not only by heavy spending, but also by a growing reliance on television and high technology described by some observers as nearly unprecedented.

The level of cable advertising in Fairfax County this year "is almost unheard-of," said Jim Hughes, advertising sales manager for Cox Communications, which provides cable to 243,000 households in Fairfax. "This is the busiest we've ever been on the local level."

In the two hottest races--Republican state Sen. Jane H. Woods against Democratic challenger Leslie L. Byrne, and Republican Scott T. Klein vs. Democrat Kristin J. Amundson for a vacant House seat--each candidate has spent about $25,000 on cable thus far, Hughes said. Others with cable ads--whose air time can cost up to $170 for a 30-second spot in prime time--include Republican Thomas M. Bolvin and Democrat James E. Mitchell III, who are challenging House incumbents in Fairfax; Republican Sheriff Carl Peed; and Tina Trapnell, a Republican candidate for the Board of Supervisors.

In Reston, which has its own cable company, Hunter Mill District Supervisor Robert B. Dix Jr., a Republican, and his Democratic challenger, Catherine M. Hudgins, are airing ads on Jones Communications.

So far, none of the candidates has advertised on broadcast television, which charges thousands of dollars per spot. That, and the fact that TV advertising blankets a wide area, not just a distinct district, makes it less cost-effective in local races.

For Jeannemarie Devolites, a Northern Virginia Republican seeking reelection to the House of Delegates, videos are the answer. Devolites mailed 15,000 professionally produced videocassettes to voters in the 35th District, at a cost of $25,000. The five-minute video mimics the biographical films shown at national political conventions, with narration by Rep. Thomas M. Davis III (R-Va.), photos from Devolites' childhood and testimonials from constituents.

Devolites said the videotape cost the equivalent of two campaign mailings and "seems to be more effective. People tend to watch it, whereas I think a lot of the paper mail gets pitched right into the trash can."

So far, she said, only one video has been returned--by an elderly woman who didn't have a VCR.

Another emerging campaign tool is to place ads in the growing number of foreign-language newspapers, many of whose readers are U.S. citizens.

"The concentration . . . in Northern Virginia is significant, and those people are voting more and more as they become more acclimated to America," said Justin Brasell, who is managing Woods's campaign, which is advertising in Korean, Vietnamese and Hispanic newspapers and has translated its brochures into other languages.

Even at the local level, campaigning is "less and less a place for amateurs," said Robert D. Holsworth, a political scientist at Virginia Commonwealth University. Odd-year elections often have low voter turnout, he noted, which "puts a premium on the technical skills of identifying your voter base" and getting people to the polls.