President Obama launched (another) rhetorical offensive in the fight to convince the public of the benefits of his health-care law on Thursday, delivering a speech highlighting the rebates that many Americans are receiving from their insurance companies.

Of the opposition to the law -- particularly within House Republican circles -- Obama said: “We’re just going to blow through that stuff and keep on doing the right thing for the American people."

Judging from polls, Obama shouldn't expect to blow through much of anything when it comes to health-care law, however. The Kaiser Family Foundation has been tracking the popularity -- or, perhaps better put, unpopularity of the bill-now-law for quite some time. Here's their data.

Since the end of 2010, those viewing the law unfavorably have -- with a handful of exceptions -- always outpaced those who see it in a favorable light. In June, 43 percent regarded the law unfavorably while just 35 percent had a favorable view of it. (Worth noting: Eight percent of those who had an unfavorable view of the law held that view because it didn't, in their minds, go far enough to overhaul the health-care system.)

"Views continue to diverge by partisan affiliation, with a majority of Democrats in favor of the law, a majority of Republicans opposed, and independents mirroring the public overall and titling negative," wrote the folks at Kaiser in a memo detailing their June results.

Looking at the data, it's readily apparent that views about the law have cemented in place. When that sort of thing happens in public opinion, virtually no external event -- no matter how dramatic or seemingly important -- can change perceptions in any statistically meaningful way. (One foreign policy example: Once the public soured on the war in Iraq, there was nothing anyone could do to change that sentiment.)

The White House has learned that lesson the hard way on health care. Time after time, once the bill became law, those close to President Obama insisted that the changes in health care would grow more popular as it began to be implemented and the partisan back and forth died away.

Of course, the partisan back and forth never died down -- House Republicans voted to repeal it for the 39th time earlier this week --  and even as the law began to be implemented views didn't change all that much.

And so, President Obama's speech today will almost certainly not move the needle on the issue. People who already like the law will still like it. Those who don't won't.