The conundrum facing the White House and congressional Democrats on the new health care law is being framed in most accounts as a classic tradeoff of politics and policy. Many Democrats dearly want to vote for a revision that would allow people to stay on individual insurance plans that insurers are now cancelling, to quell a political storm that has coincided unhappily with the troubles of the healthcare.gov Web site where these people were supposed to be able to sign up for new and hopefully better plans. As has been noted, though, letting people keep those cancelled plans could have deleterious policy consequences if it means keeping the relatively young and/or healthy out of the new insurance exchanges.

But what if this is a mistaken opposition? What if, in fact, a major revision of the law would turn out to be just as politically risky for Democrats, if not more so?

The factor that is not being considered enough here is timing—no surprise, perhaps, in a town with famously short-term mindset. No, it’s not fun for Democrats to see President Obama’s approval rating at 39 percent and their big lead on the generic congressional ballot evaporate to nothing. But the midterm elections are still nearly a year away, despite what you might believe from the tinsel-in-October sort of stories that the political press is already pumping out. You know what is a lot closer to the midterm elections? October 2014, which is when insurers will be announcing premiums for 2015.

And that’s where the policy “fix” Democrats are now contemplating comes in. Allowing people who had their plans canceled to keep them means that many of them will not be going into the new exchanges. To the extent that the people who had the canceled plans were younger and/or healthier than the norm—after all, insurers pre-ACA could easily screen out the older and less healthy—their staying out of the exchanges will result in an insurance pool weighted toward costlier enrollees, the dreaded “adverse selection.” This would raise the likelihood that insurers would be raising rates on the exchange—which came in at relatively competitive levels for 2014, all in all—to much higher levels for 2015. And again, those rates would be announced in October 2014, just before the midterms. Health insurance industry lobbyist Karen Ignagni warned as much in a statement today in response to Obama’s proposed fix to allow insurers to keep offering the canceled plans: “Changing the rules after health plans have already met the requirements of the (Obamacare) law could destabilize the market and result in higher premiums.”

Jonathan Chait is farsighted enough to get this: