The Affordable Care Act was supposed to be a slam-dunk issue for Republicans in this fall’s elections. Karl Rove told us so in April, writing that “Obamacare is and will remain a political problem for Democrats.”

So how’s that Obamacare thing working out for the GOP?

The most significant bit of election news last week was the decision of Sen. Mark Pryor, the embattled Arkansas Democrat, to run an ad touting his vote for the health care law as a positive for the people of his increasingly Republican state.

Pryor’s ad is so soft and personal that it’s almost apolitical. After his dad, the popular former senator David Pryor, tells of his son’s bout with cancer, he notes that “Mark’s insurance company didn’t want to pay for the treatment that ultimately saved his life.” The picture has widened to show Mark Pryor sitting next to his father. “No one should be fighting an insurance company while you’re fighting for your life,” he says. “That’s why I helped pass a law that prevents insurance companies from canceling your policy if you get sick, or deny coverage for preexisting conditions.”

Who knew a law that critics claim is so dreadful could provide such powerful reassurance to Americans who are ill?

Democrats have never fully recovered from the Obama administration’s lousy sales job for (and botched rollout of) what is, legitimately, its proudest domestic achievement. That’s one reason Pryor doesn’t use the word “Obamacare” in describing what he voted for. Another is that, in many of the states with contested Senate races this year, most definitely including Arkansas, President Obama himself is so unpopular that if you attached his name to Social Security, one of the most popular programs in American history would probably drop 20 points in the polls.

So, as the liberal bloggers Greg Sargent, Brian Beutler and Steve Benen have all noted, Republicans would much prefer to run against the law’s name and brand than the law itself. They also really want to avoid being pressed for specifics as to what “repealing Obamacare” would mean in practice.

As one Democratic pollster told me, his focus groups showed that when voters outside the Republican base are given details about what the law does and how it works, “people come around and say, ‘That’s not so bad, what’s everybody excited about?’ ”

This consultant says of Democrats who voted for the law: “You’re going to be stuck with all the bad about this but not benefit from any of the good unless you advertise” what the Affordable Care Act does. This is what Pryor has decided to do.

In fact, according to Gallup, Arkansas is the No. 1 state in the country when it comes to reducing the proportion of its uninsured since the main provisions of the ACA took effect. The drop was from 22.5 percent in 2013 to 12.4 percent in 2014. The No. 2 state is Kentucky, where the uninsured rate fell from 20.4 percent to 11.9 percent. What they have in common are Democratic governors, Mike Beebe in Arkansas and Steve Beshear in Kentucky, committed to using Obamacare — especially, albeit in different ways, its Medicaid expansion — to help their citizens who lack coverage. Beshear has been passionate in selling his state’s version of Obamacare, which is called Kynect.

Kentucky also happens to be the site of another of this year’s key Senate races. Democrat Alison Lundergan Grimes is giving Republican leader Mitch McConnell what looks to be the toughest reelection challenge of his 30-year Senate career.

The Bluegrass State is particularly instructive on the importance of labeling and branding. A Public Policy Polling survey this month found that the Affordable Care Act had a net negative approval rating, 34 percent to 51 percent. But Kynect was rated positively, 34 percent to 27 percent. Grimes and the Democrats need to confront McConnell forcefully on the issue he has tried to fudge: A flat repeal of Obamacare would mean taking insurance away from the more than 521,000 Kentuckians who, as of last Friday, had secured coverage through Kynect. How would that sit with the state’s voters?

Election results, like scripture, can be interpreted in a variety of ways. You can bet that foes of expanding health insurance coverage will try to interpret every Republican victory as a defeat for Obamacare. But as Mark Pryor knows, the president’s unpopularity in certain parts of the country doesn’t mean that voters want to throw his greatest accomplishment overboard — even if they’d be happy to rename it.

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