Nearly a year ago, the Campaign Media Analysis Group at Kantar Media, which tracks advertising spending, found that since the Affordable Care Act was signed into law, critics have outspent supporters by a greater than five-to-one margin.

As it turns out, the re have been quite a few ads since last June, and the same researchers have revised their tally

The report, released Friday by nonpartisan analysts Kantar Media CMAG, estimates that $445 million was spent on political TV ads mentioning the law since the enactment of the Affordable Care Act in 2010. Spending on negative ads outpaced positive ones by more than 15 to 1. Outside of Social Security and Medicare, “no other law has come close to these amounts, much less within such a short period of time,” said Elizabeth Wilner of Kantar Media. “It speaks to the intensity of the opposition among the ACA’s political critics” and their belief that the health care issue will benefit their party in this year’s elections, she said.

More specifically, according to the report, ACA opponents have spent $418 million on 880,000 commercials , as compared to $27 million on 58,000 positive ads from the law’s proponents. This includes advertising on all local television markets, national broadcast networks, and cable.

It doesn’t include online ads, though it’s hard to imagine how they would help narrow the imbalance.

Assuming the research is accurate, it would help explain a few things. For years, there’s been a lingering question underscoring public attitudes on “Obamacare”: if the polls showed public demand for health care reform going into the reform fight; Democrats approved a moderate law built on bipartisan ideas; and polls show broad support for the law’s provisions, why does the public still disapprove of the Affordable Care Act?

Perhaps because they’ve seen some of the 880,000 attack ads.

In fact, maybe I’m the oddball on this, but given the one-sided advertising, shouldn’t the ACA be a lot less popular?

Consider what a 15-to-1 gap looks like on a pie chart.

To be sure, the Affordable Care Act isn’t winning any popularity contests. Its support has grown steadily over the last several months, but in the vast majority of surveys, critics still easily outnumber backers. According to the most recent data, sup port tends to be in the low- to mid-40s, a figure that’s shown steady improvement.

I hate to break this to the right, which has literally and figuratively invested so much in this fight, but after outspending proponents 15 to 1, the ACA is holding up pretty well when it comes to public attitudes.

Look, there’s no mystery as to why these ads aired in the first place: in general, television advertising is a very effective medium. When the right spends hundreds of millions of dollars to air misleading attack ads, desperately trying to convince Americans to hate health care reform, it’s going to have an effect. Indeed, most of the public won’t know better – they don’t follow politics closely; they’re not policy wonks; and they’ve been inundated with “You should hate Obamacare” messaging for more than four years. Clearly, this will turn a whole lot of folks against the law, even if these same people love the provisions of the law they claim to dislike.

But as a long-term proposition, conservatives must realize at a certain level that time is no longer on their side. They threw everything they had at “Obamacare,” up to and including outspending their opponents 15 to 1, and the law is still in the low- to mid-40s and is still growing more popular.

That’s hardly a victory $418 million and 880,000 commercials later.

Update: Some friends on the right are suggesting that the study from the Campaign Media Analysis Group at Kantar Media paints an incomplete picture, since the 15-to-1 results point only to political advertising. What about the $249 million spent by the government and insurance companies to encourage enrollment?