Why that one Democratic Obamacare ad didn’t signal a new trend

“When Sen. Mark Pryor of Arkansas went up with a television ad last week alluding to some benefits of Obamacare, partisans on both the left and the right saw the spot as a sign that vulnerable Democrats might finally be embracing the polarizing health-care overhaul in their campaigns.
But in the days since, it’s become clear: there’s little evidence that the hotly debated law is on its way to becoming a central Democratic talking point heading into the fall campaign.
“It’s basically the first pro-Obamacare ad we’ve seen by a vulnerable Democrat for months,” said Elizabeth Wilner, senior vice president of Kantar Media Ad Intelligence, whose Campaign Media Analysis Group tracks political advertising. “It’s like seeing a unicorn – it just doesn’t happen very often.””