Why do Republicans keep voting to repeal Obamacare? For one thing, we journalists keep writing about it.
Here's a chart from Google Trends, which tracks news headlines over time. I typed in "Obamacare repeal," and here's what it came back with:
More than a year later, a July 2012 vote to repeal Obamacare — right after the Supreme Court upheld the law — got just as much coverage, even though it was no longer much of a novelty. And back in May, when the House voted for the 37th time (or 38th, depending on whose count you use) to overturn the law, there was still a pretty significant spike in interest.
The House votes aren't going to change policy. Not every one of them generates a large amount of media coverage – only about one in 10 gets major media attention. But even three years after the Affordable Care Act became law, the votes do appear to have some staying power, and the ability to grab a not-insignificant amount of attention.