The most important political and policy news of the day is Gallup’s new finding that the rate of uninsured Americans has now fallen in three straight Gallup surveys:

The percentage of Americans without health insurance continues to fall, measuring 15.9% so far in 2014 compared with 17.1% in the fourth quarter of 2013. [...]

The uninsured rate has been declining since the fourth quarter of 2013, after hitting an all-time high of 18.0% in the third quarter. The uninsured rate for the first quarter of 2014 so far includes a 16.2% reading for January and 15.6% for February.

The uninsured rate for almost every major demographic group has dropped in 2014 so far. The percentage of uninsured Americans with an annual household income of less than $36,000 has dropped the most — by 2.8 percentage points — to 27.9% since the fourth quarter of 2013, while the percentage of uninsured blacks has fallen 2.6 points to 18.3%. Hispanics remain the subgroup most likely to lack health insurance, with an uninsured rate of 37.9%.

The percentage of uninsured has declined across all age groups this year, except for those aged 65 and older. The uninsured rate for that group has likely remained stable because most Americans aged 65 and older have Medicare. The uninsured rate among 26- to 34-year olds and 35- to 64-year olds continues to decline — now at 26.6% and 16.3%, respectively.

To be sure, we still don’t know for certain whether Obamacare is the reason for this, as I noted the last time Gallup issued a similar finding. But Gallup has now found this three straight times, which suggests it may not be statistical noise and could be a trend, though caution is still in order. As Kaiser’s Larry Levitt told me last time:

“It’s an early possible sign of success. There’s been a lot of uncertainty about the effect the ACA is having on the number who are uninsured. Clearly people are signing up, and clearly Medicaid coverage is expanding. But many had their policies canceled. This is the first sign that the net of all that is still likely a decrease in the number of uninsured — it may be moving in the right direction.” [...]

“We’ve been fighting about this law in the realm of  speculation for years. What we should be looking at primarily is, are more people getting covered? That’s the law’s fundamental aim. We will now start to see real data.”

GOP certainty that the law is collapsing — and will deliver Republicans the Senate — deepened earlier this month after the administration announced its latest delay. But today’s Gallup numbers remind us we’re inexorably moving into the realm of the concrete when it comes to the most important Obamacare metric of all — how many people are gaining heath care coverage.

As Gallup has noted, if this trend continues, it will increasingly suggest Obamacare may be the reason for it. While the short term politics of the law will continue to be tough going for Dems, a continuation of this trend could begin to scramble the political calculus. We’re already seeing the GOP repeal stance begin to crack up as enrollment mounts and local GOP officials and GOP candidates embrace versions of the Medicaid expansion for their states; a continued fall in the uninsured could make it increasingly difficult for Republicans to continue pretending the law’s beneficiaries simply don’t exist.

* DEMS SEIZE ON MEDICAID EXPANSION: The Hill’s Jonathan Easley reports on something that really deserves more attention: Even though the Beltway narrative has it that Obamacare is uniformly bad for Dems, they see the Medicaid expansion as a key issue in this year’s elections. The Louisiana example:

Sen. Mary Landrieu has launched a petition on her website urging Gov. Bobby Jindal to agree to the expansion, which she argues would bring health insurance to more people who cannot afford it. The issue is giving Landrieu a chance to run not only against her GOP opponent Rep. Bill Cassidy, who opposes the extension, but against Jindall as well. She argues the expansion would close “the Jindal Gap.” [...]

Americans for Prosperity, the group backed by the billionaire Koch brothers, is making opposition to the expansion a top priority through a “Stop the Madness” ad campaign.

And so the Medicaid expansion — and the Koch-backed AFP’s support for it — will become a major issue in the Senate race when it’s debated there this spring. Meanwhile, the GOP Senate candidate in Michigan came out for the expansion after Dem Gary Peters called her out over it, and in New Hampshire, which is moving the expansion forward, it could become an issue in House races.

* THE LATEST ON FLORIDA’S SPECIAL ELECTION: The latest numbers on absentee ballots and early voting in the special election in Florida’s 13th district show Republicans leading Dems in total ballots cast, 42-39. Republicans expanded their lead last week and into the weekend, leading by five on Saturday, strengthening their position. But yesterday Dems took in more of the early vote, shrinking the lead to three.

*NON-AFFILIATED VOTERS WILL DECIDE FLORIDA ELECTION: For context, see this Tampa Bay Times piece, which notes Republicans historically cast many more votes in this district, yet Dems still win by over-performing among independents and swing voters, as in the 2010 governor’s race and in 2012:

In 2012, Republicans had cast nearly 11,000 more votes than Democrats by election day and then outperformed Democrats on election day by more than 9,000 votes. Barack Obama still narrowly won the district. In 2010, Republicans had a nearly 12,400-vote lead prior to election day and then on election day cast more than 8,600 more votes than Democrats. Sink still narrowly beat Republican Rick Scott in the district.

Democrats expect Republicans to have a registration edge of at least 10 points, but can win anyway if — again, if — Dem Alex Sink gets enough crossover votes and independents. This is a reminder that vagaries of turnout will decide this thing on the margins, so again: ignore the hype about what it means, whoever wins.

* GOP CANDIDATE CLOSES WITH APPEAL TO MIDDLE: Related to the above: Bloomberg News reports that the closing ad for Republican David Jolly makes an important change from an earlier spot: it removes the word “conservative.” Jolly had been running a campaign designed to rev up the base, but now it appears he’s decided he needs to appeal to those independents and swing voters to win.

* DEMS KEEP UP ASSAULT ON KOCH BROTHERS: Vulnerable Senator Mark Begich of Alaska is up with a new ad hitting back at an Americans for Prosperity spot attacking him with the false claim that he supports a “carbon tax.” The ad spotlights the closure of a local oil refinery owned by Koch Industries:

“They come in to our town, buy our refinery,” one man says, while another follows by saying the company is “just running it into the ground.”

“I don’t go down and tell them what to do; I don’t expect them to come to Alaska and tell us what to do,” one man says.

As reported here last week, attacks on the Koch brothers are all about creating a narrative framework within which voters might understand why Republican candidates support policies that aren’t in their — or their states’ – interests. Instead, they are beholden to an agenda pushed by out of state interests.

* NO, REDUCING INEQUALITY DOESN’T IMPEDE GROWTH: Paul Krugman takes on the oft-repeated claim on the right that taking action to reduce inequality will have a negative impact on economic growth, discussing two studies that show the impact is negligible. Also, this:

Think, in particular, about the ever-popular slogan that we should seek equality of opportunity, not equality of outcomes. That may sound good to people with no idea what life is like for tens of millions of Americans; but for those with any reality sense, it’s a cruel joke. Almost 40 percent of American children live in poverty or near-poverty. Do you really think they have the same access to education and jobs as the children of the affluent? In fact, low-income children are much less likely to complete college than their affluent counterparts, with the gap widening rapidly.

And, of course the claim that Dems want “equality of outcomes” is just a big falsehood designed to obfuscate the true nature of the differences between the parties on this issue.

* HOW TO EVALUATE PAUL RYAN’S NEW POVERTY AGENDA: E.J. Dionne makes it simple:

So far, it’s hard to find evidence of any fundamental rethinking. Conservatives want to say that they’re devoted to more than the well-being of the wealthy, but their tax and regulatory policies remain focused on alleviating the burdens on the “job creators,” i.e., the rich. They say they want to do better by the poor, but the thrust of their budgets is to reduce assistance — sometime savagely, as in the case of food stamps — to those who need it. Ryan no longer refers to social programs as a “hammock” for the idle, but he still wants to cut them.

There’s no other way to make the math work, given all the ways stated GOP priorities remain unchanged.

What else?

Greg Sargent writes The Plum Line blog, a reported opinion blog with a liberal slant -- what you might call “opinionated reporting” from the left.