PORTLAND, Ore. (Map, News) - Flush with cash, the Democratic Senatorial Campaign Committee has made their first television ad buy of 2008, spending $100,000 to take a shot at Oregon Republican Gordon Smith.

The ad comes on the heels of Smith's own ad, released last week, that dinged the top two Democrats competing for his seat: Oregon House Speaker Jeff Merkley and Portland lawyer Steve Novick.

And it's yet more evidence that Oregon's Senate seat will be a key priority for national Democrats this fall, amid a crowded electoral map that suggests nearly a dozen different Senate races could be competitive.

Democrats think they've got a good shot at open Senate seats in Colorado, Virginia and New Mexico, and are gunning for Republican incumbents in Maine, Minnesota, New Hampshire, Alaska, Kentucky and Oregon.

Of those states, Oregon has the most closely contested Democratic primary. Merkley and Novick have been slugging away at each other in recent weeks; the DSCC ad is a clear pitch to shift the focus from inter-party fighting back to Smith and his record.

And while the DSCC has made it clear that they would prefer Merkley, whom they recruited to run against Smith, to emerge as the winner of the May 20 primary, the new ad avoids taking sides between Merkley and Novick, instead focusing squarely on Smith.

"In Washington, Smith has stood with George Bush and the special interests," the ad's narrator intones, over a picture of Smith standing at Bush's side, "Supporting tax breaks for companies that ship jobs overseas, tax cuts for the wealthy, tax giveaways to big oil."

Matt Miller, a spokesman for the DSCC, said the ad was launched after Smith began running an ad last week attacking Merkley for taking contributions for his federal race while the state Legislature was in session in February, and Novick for his advocacy on tax issues.

"We think that he is one of the most vulnerable incumbents in the country, and the fact that he is already on the air attacking his opponents is a sign of that," Miller said.

Smith's campaign reacted quickly to the ad, sending out a plea for donations to supporters, even though Smith has already raised $8.3 million, far, far more than either of his Democratic rivals.

R.C. Hammond, a spokesman for Smith, said Smith has "a fundamental belief that cutting taxes is good for families, that leaving money in people's pockets will do more good most of the time than sending it to Washington, D.C. It is a fundamental black-and-white difference between Senator Smith and his opponents."

The DSCC has far outraised its Republican counterpart this year, with $37.8 million in the bank, more than double the National Republican Senatorial Committee's $17.3 million.

This isn't the committee's first ad buy of this election cycle. In July 2007, the committee spent $100,000 to buy ads in four states - Kentucky, Maine, Minnesota and New Hampshire - to pressure Republicans facing re-election over the Iraq war.

Elsewhere on the airwaves, the Merkley campaign on Wednesday began airing a commercial jabbing at Novick for blog postings criticizing prominent Democrats, written before he was a Senate candidate. The ad also portrays Merkley as a bridge-builder.

"As a political consultant, he tears people down in order to change their views," said Matt Canter, a spokesman for Merkley. "Jeff Merkley has a very different leadership style, of bringing people together to make change."

But Novick's campaign manager, Jake Weigler, said the ad pulls a few words from lengthy blog postings, and presents them out of context. For example, Novick's query about whether Obama could be classified as a "captive-of-special-interests fraud" came during an examination of Obama's support for the corn-based ethanol industry, which has come under fire for its high environmental price tag.

"The Merkley campaign is so desperate that they have decided to launch a full-scale negative barrage against us," Weigler said.