On Monday, House Speaker John Boehner repeated the same repeal-and-replace Obamacare promises that he’s been making to the American people for four or five years now:

“House Republicans will continue to work to repeal this law and protect families and small businesses from its harmful consequences,” he said in a statement. “We will also continue our work to replace this fundamentally flawed law with patient-centered solutions focused on lowering health-care costs and protecting jobs.”

But the truth is, he will achieve neither repeal nor replacement. The numbers, the march of time and his party’s own stubborn ideology have slammed those doors shut.

Let’s talk immediate numbers first: With a surge of signups at the March 31 deadline, Obamacare enrollment numbers are now “significantly” above the most recent target of six million and may now reach the original goal of seven million for 2014. That seemed impossible last fall, in the midst of the program’s disastrously incompetent rollout, but the rebound has been impressive and suggests a real public demand. However, the larger problem for Republicans comes in the next couple of years. According to a February report from the Congressional Budget Office, “more people are expected to respond to the new coverage options, so enrollment is projected to increase sharply in 2015 and 2016” over 2014. How sharply? According to CBO, enrollment through Obamacare exchanges will more than triple by 2016, to 25 million. When you add the 12 million benefiting from Obamacare’s expansion of Medicaid, that’s 37 million Americans who by 2016 will have insurance through the Affordable Care Act. Two-thirds of them would not have coverage at all without the law. Now, I’m no Karl Rove, but it seems to me that a Republican presidential candidate who runs on a platform of stripping health insurance from more than 25 million Americans is going to have an uphill battle, to say the least. That’s particularly true if Republicans still don’t have a program of their own for providing that coverage, and there’s no sign of such a miracle occurring.

The reason is obvious: The GOP has been unable to offer an alternative means of expanding insurance coverage, particularly for lower-income working Americans, because they are fundamentally, philosophically opposed to expanding insurance coverage for lower-income Americans. Period, end of story. What other reason could there be for preventing some 500,000 Georgians from participating in Medicaid, as this state’s leadership has done?

By now, the trick of promising but never delivering a replacement plan is wearing thin on voters, and polls are beginning to reflect that reality. Last week, the latest Kaiser Foundation health-care tracking poll reported that only 29 percent of Americans — essentially, the GOP base — still want to repeal Obamacare while 59 percent of Americans want to keep it or reform it.

Likewise, an ABC News/Washington Post poll released Monday reports that, for the first time, slightly more Americans say they support Obamacare (49 percent) than oppose it (48 percent). That’s a big swing from the same poll in November, when just 40 percent supported Obamacare and 57 percent opposed it.

The poll also found that 36 percent of conservatives now support the law, up from 17 percent last fall. Support also jumped 16 points among Americans ages 18-39, a demographic critical to the program’s success. Fifty-four percent now say they support it, and according to insurers, that support is reflected in higher enrollment numbers for young people.

Admittedly, the ABC/WashPo numbers still sound a little high — it will be interesting to see if they are confirmed by other pollsters. But the direction in which public opinion is headed seems clear, and it calls into question the effectiveness of the Republican strategy for the 2014 midterms.

Back in the fall, when they committed to using Obamacare as the one and only issue this year, Republicans were certain that the program was headed into the dreaded death spiral and that public opinion would swing even stronger to their side.

Neither has happened.