Planned Parenthood and EMILY's List, a Democratic political action committee that supports female candidates, teamed up for an ad hitting Republican Rob Cornilles as too extreme on women's issues and calling attention to his opposition to abortion rights.

"These decisions are best left to a woman, her family and her faith, not politicians," the narrator says in the ad.

An EMILY's List spokeswoman confirmed the groups are spending in the low six figures for the ads attacking Cornilles and promoting Democrat Suzanne BonamiciSuzanne Marie BonamiciCongress — when considering women’s health, don’t forget about lung cancer Overnight Energy: Two top Pruitt aides resign at EPA | 17 states sue EPA over car emissions rules | Volkswagen to pay West Virginia .5M over emissions cheating House Dems question Pruitt over possible plans for Tulsa EPA office MORE, whom EMILY's List has endorsed.

Meanwhile, Cornilles's campaign is spending about $100,000 for ads targeting Bonamici, according to the Rothenberg Political Report. Although Cornilles also went on the air in early December, the new ad represents his first negative ad directly attacking Bonamici. Earlier ads were biographical spots — some featuring his wife — intended to introduce him to Oregon voters.

Cornilles's new ad extends the strategy he's deployed against Bonamici for most of the campaign, juxtaposing his record on job creation with hers and portraying her as too liberal for the district's voters. But that's an uphill battle for a Republican in the heavily Democratic district that Rep. David Wu (D-Ore.) represented until he resigned in June amid a sex scandal.

"Incredibly, Bonamici can't recall ever voting against a tax increase or fee hike, and she has no record of job creation," Cornilles's ad says.

Adding to the countervailing messages cluttering Portland's airwaves are well more than $1 million in ads paid for by the Democratic Congressional Campaign Committee. Democrats in Washington are eager to see Bonamici win by a large margin in part to bolster their argument that Democrats are in prime position to retake control of the House when the rest of the chamber is up for reelection in November.

The election for Wu's old seat will be held on Jan. 31, but is being conducted entirely through mail-in ballots, making the air war early in the month even more important.

Read a full breakdown of the race here.

Watch the ad targeting Bonamici:

Watch the ad targeting Cornilles: