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A Democratic-leaning online group will run television commercials in 17 presidential battleground states starting Thursday to counter President Bush's multimillion-dollar advertising blitz that will begin the same day.

The MoveOn.org Voter Fund (search) has been airing commercials assailing Bush for months in several swing states, but this $1.9 million, five-day effort will be its most far-reaching. The ads will ensure that there is a Democratic presence on the TV airwaves in key states as Bush begins to make his case for re-election.

John Kerry (search), the Democratic front-runner, is considering a modest response designed to put the White House on the defensive, advisers say, but the Democratic National Committee (search) is waiting until there is a nominee before it starts running ads. That leaves outside groups like MoveOn, acting independently of the campaign, as the primary Democratic voice.

Other such groups, nicknamed "527s" after the section of the tax code that applies to them, and traditional lobbying organizations may follow soon.

Bush's campaign plans to spend a large part of its $100 million war chest on ads during spring and summer. It will begin running a positive ad about leadership Thursday on broadcast stations in 17 swing states and nationally on cable networks targeting its GOP base. The campaign is slated to spend at least $4.5 million on cable alone over the next three weeks.

In most states, MoveOn will run a new ad that takes Bush to task for his economic policies, including overtime pay and outsourcing jobs. In others, the group will run a previously released spot that shows images of children toiling on a grocery line and in a tire factory coupled with the text, "Guess who's going to pay off President Bush's $1 trillion deficit?"

Ads will run over five days at medium levels on broadcast stations in 67 media markets in Arizona, Arkansas, Florida, Iowa, Maine, Michigan, Minnesota, Missouri, New Mexico, New Hampshire, Nevada, Ohio, Oregon, Pennsylvania, Washington, West Virginia and Wisconsin. The television industry estimates that the average viewer in each media market would see a MoveOn spot about five times during the group's ad run.

"We're really stepping up our efforts to make sure our members' voices are heard," Wes Boyd, the group's founder, said Tuesday. "We are trying to get these messages out about these fundamental issues."

Boyd said the buy may be extended after the group sees how the political landscape looks next week.

MoveOn started running anti-Bush ads in September. The group has spent at least $6 million of the $10 million it says it has raised so far for advertising.

It has broadcast some of the election season's most critical TV commercials against the president, taking him to task for the Iraq war, the economy, job losses and prescription drug policies. The ads usually label the incumbent Republican a "misleader."

Two Silicon Valley entrepreneurs founded the group during the Clinton impeachment debate as an online petition urging Congress to censure him and move on to other business. It claims 2.3 million members nationwide.