Democratic groups and liberal political action committees ranging from EMILY's List and Planned Parenthood to the Democratic Congressional Campaign Committee (DCCC) have already dropped well over a million on the race. Democrats had expected national Republicans to stay out of the race in a district that President Obama won by 25 points in 2008.


"You have to look no further than how much the Democrats are spending to see that Rob has made this into a competitive race," said an NRCC spokesman.

Cornilles’s campaign did not respond to a request for comment.

For months, Republicans in Oregon had quietly noted that unlike Bonamici, whose candidacy was bolstered by heavy involvement from national Democrats, the NRCC had left Cornilles largely to his own devices, keeping its role limited to the periodic distribution of press releases touting his candidacy.

But the NRCC investment also comes as Cornilles’s campaign has been circulating a new internal poll from a GOP pollster showing that he is now within four points of Bonamici, a former state lawmaker. Earlier polls had suggested Bonamici held a double-digit lead over her Republican opponent.

Democrats said they always expected the race would tighten up at the end, but also questioned the accuracy of the poll by the Cornilles campaign.

Democrats have framed their heavy investment in the race as an insurance policy and a take-nothing-for-granted strategy, downplaying speculation they were concerned about a loss in a district that Wu — a Democrat — held for seven terms before resigning in July amid a sex scandal.

But with House Democrats looking ahead to November and their fight to retake control of the House, Democratic groups have sought to secure a substantial win in the Oregon race to help them make their case that American voters want to see Democrats in control of Congress.

Both sides are drawing comparisons to a Nevada special election in September that offered an opposite scenario. Republican Mark AmodeiMark Eugene AmodeiBillboards calling on House Republicans to 'do their job' follow members home for Thanksgiving Trump's defenders are running out of options Avoiding the snake in the grass: Let's not allow impeachment to divide us MORE (R-Nev.), aided by hundreds of thousands of dollars from the NRCC, finished more than 20 points ahead of Democrat Kate Marshall, who got little DCCC help in a district where the GOP was heavily favored to win.

As they look south from Oregon, Republicans are noting that, to shore up their candidate in Nevada, they spent a fraction of what Democrats have to support Bonamici. But Democrats said the last-minute spending from the NRCC was more about avoiding the impression of having left their candidate without a lifeline.

"This has sort of been saving face," said a Democratic source. "It's not a race they think they can win, but they kind of have to put something in there, because it's a Republican candidate they need to support."

This post was updated at 5:53 p.m.

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