Yesterday, state treasurer Doug Ducey won the GOP nomination for governor to replace Jan Brewer in Arizona. Brewer was one of eight GOP governors who accepted the expansion of Medicaid, something Ducey had opposed. Ducey’s comments on the subject are vague at; when asked whether he’d repeal the expansion, he bobs and weaves. And it isn’t hard to understand why.

Looking at this race in combination with other close races, you see that the politics of health care have shifted profoundly in recent months. As Democrats are stroking their chins wondering whether they can turn the Affordable Care Act into a winning issue this fall, and if so how to do it, the answer is simple: Don’t defend, attack.

Meanwhile, those reporting on these races should appreciate that the health care issue isn’t as simple as it was, where Republicans just used it to beat up Democrats. Both sides now have something to gain from talking about health care.

Everyone paid attention last week when Mark Pryor, a vulnerable Dem in deep-red Arkansas, aired an ad touting his support for the ACA. But the story quickly became all about how the ad didn’t name the law — supposedly showing that Obamacare is still a millstone around the neck of Dems everywhere.

But this analysis doesn’t reckon with the complexity of how the politics of health care are actually playing out in multiple Senate races.

There’s a paradox at the heart of the politics of the ACA: Americans like almost all the particular things the law does, but a majority disapprove of this thing called “Obamacare” that they only vaguely understand. Which is why Republicans have arrived at a strange (you might even say hypocritical) place, where they promise to repeal Obamacare, even as they mumble support for the law’s general goals and fudge on whether they’d take its benefits away from people. We certainly don’t want insurance companies to deny coverage because of preexisting conditions, they say. And of course low-income people should get help to buy health insurance. In other words, they want to repeal Obamacare, and replace it with most of Obamacare. Maybe they could just call it Reagancare?

But once they’ve come out for repeal, as nearly every Republican has, they make themselves vulnerable to attacks, particularly now that people are receiving benefits that could be taken away. A Democrat can say of her Republican opponent, “He wants to let insurance companies kick you off your health plan if you get sick,” and though the Republican might say, “Nuh-uh!” it would be true. If the Democrat is using the specifics of the ACA as a cudgel, it’s a very different debate than the one over “Obamacare.”

Which brings us back to Arizona. According to the federal government, the state increased its Medicaid and CHIP enrollment by 225,310 in the open enrollment period that ended in June. That increase of 18.75 percent was just about the same as the average for all states that accepted the Medicaid expansion (18.47 percent). If Arizona had rejected the expansion and seen their enrollment grow at the same rate as the other states that rejected it (only 4 percent), it would have meant 177,119 fewer Arizonans with health coverage.

Saying you’re going to kick a couple of hundred thousand people off their health plans isn’t a recipe for political success. That’s why Doug Ducey is fudging his plans for Medicaid, and why the chances are that if he becomes governor he wouldn’t undo it.

More Republicans at the state level are going to accommodate themselves to the reality of the ACA. We learned this week that Wyoming is considering accepting the Medicaid expansion, for the simplest of reasons: money. As one report detailed, for every dollar a state invests in the expansion, they’ll receive $13.41 in federal funds, not to mention the likely benefits that come with a smaller uninsured population. You’d have to be crazy to turn down that deal, or just really, really committed to making sure poor people don’t get health coverage.

As Sam Wang recently detailed, there are nine GOP governors running for reelection this year. Five resisted Medicaid expansion and four accepted it. According to polls, “Republican governors who bucked their party’s stance and accepted the policy are faring better with voters — in these races, an average of 8.5 percentage points better.” The Medicaid expansion may not be responsible for that difference, but still: The Republicans who took the expansion are doing quite well.

One Republican candidate after another is fudging his or her actual health care positions, just as Doug Ducey has done on the Medicaid expansion.  The problem: Those different races tend to be mostly invisible to people in Washington until somebody puts up an ad we can watch, and it’s true that Dems haven’t aired many ads about the ACA. But that could change soon, and the coverage of this issue ought to reflect the nuances and complexities here. Health care may not be an unequivocal winner for Dems, but they’re discovering that it isn’t a uniform loser and can at times strategically be used to their advantage.