A mini-bombshell from the Daily Caller. The only poll of the race taken before this came at the start of April and had Monica Wehby trailing Jeff Merkley by 12 points. A month later, the Caller finds her up 40/39 among “active voters,” i.e. newly registered voters plus longtime registered voters who voted in one of the last two elections. What’s changed? Maybe nothing; with so few polls to go by, it could be that one of these is an outlier. Or, it could be that Wehby’s much-praised “Trust” ad that made the rounds a few weeks ago raised her name recognition enough to make her competitive with a weak incumbent.

The Caller’s headline for this story is “Wave Year?”, with good reason. If we see another poll like this out of Oregon, I might have to break out the old “Waterloo” video.

Wehby, a Portland-based pediatric neurosurgeon, received the support of 40 percent of respondents, while an additional five percent say they are leaning towards supporting the first-time candidate. Merkley, who was elected to the Senate in 2008, garners the support of just 39 percent of respondents, with two percent saying they lean towards supporting him…

The poll also indicates that a plurality of voters in the deep-blue state see Obamacare as a mostly failed venture. Forty-six percent of respondents said Obamacare and Cover Oregon, the state’s disastrously flawed health care exchange, were failures, while 17 percent said they were successes, and 37 percent said they were “somewhere in between.”

Wehby, a moderate, just landed Mitt Romney’s endorsement. Peek into the crosstabs and you’ll see some numbers that look off, like Wehby trailing Merkley by less than six points among black voters and leading Merkley by nearly 10 points among Latinos in a very Democratic state. What’s up with that? As a few people on Twitter pointed out, it’s a function of the state’s demographics: Oregon is overwhelmingly white, which means that subsamples involving blacks and Latinos in polls of the state will necessarily be tiny and involve a large margin of error. Merkley’s surely leading Wehby comfortably among both demographics in reality — but because those demographics are such a small part of the overall electorate, the error doesn’t affect the topline numbers much.

This is interesting, though:

As you saw in the “Trust” ad and as you’ll see again below, advertising for Wehby is aimed squarely at peeling off women voters from Merkley. In fact, though, she’s crushing him among men and trails (albeit not badly) among women. If her ad strategy starts to work and she can keep it close among women, Merkley’s done. The only thing that might save him under those circumstances is a turnaround in the ObamaCare numbers — and remember, when it comes to O-Care, Oregon’s no ordinary state.