This Friday, House Republicans are expected to vote on a proposal — championed by GOP Rep. Fred Upton — that would allow insurance companies the option of continuing all existing health plans for a year, in response to the loss of plans that has taken place despite Obama’s vow otherwise. The White House points out that this will undermine the law.

Dem leadership aides have predicted that some House Dems will vote for the plan. And CNN’s Dana Bash stirred up chatter today when she Tweeted that “lots” of House Dems will vote for it if the White House has not put forth its own fix by the end of the week — in effect giving the White House a deadline. Obviously, “a lot” of Dems voting for this proposal would constitute another major Obamacare headache.

House Democratic leaders are privately warning rank and file Dems that a vote for this bill — and other anti-Obamacare legislation — could alienate leading Democratic donors heading into 2014, a source familiar with internal discussions tells me. “Votes against the Affordable Care Act are going to turn off a lot of these top national progressive donors,” the source said in characterizing the arguments.

Dem leaders are also pressing members internally with the case (which they are also making publicly) that the Upton plan would essentially preserve the worst aspects of the individual insurance market — allowing discrimination against people with preexisting conditions and allowing higher charges to women — thus undermining Obamacare’s protections, the source says.

The source adds that Bill Clinton’s widely reported comments today are not making this any easier for Democrats. Clinton said that “the president should honor the commitment” made to people who want to keep their insurance, “even if it takes a change in the law.” This sounded a bit like Clinton was trying to echo Obama’s own similar comments to NBC last week — in which he agreed a fix was necessary for these folks and said such a fix is forthcoming — but made a hash of it. However, Clinton’s spokespeople have not clarified the remark — which has also been distinctly unhelpful for Dems, according to my source — and so the damage is done.

Any such House bill to undermine Obamacare, of course, is dead on arrival in the Dem-controlled Senate. Some Democrats up in 2014 are pressing forward with their own efforts to minimize the political fallout of Obamacare’s problems, such as Senator Mary Landrieu’s bill to allow people to keep their insurance and Senator Kay Hagan’s call for a “probe” into what has gone wrong with the law. Republicans are having a grand old time pointing to these Dem proposals as proof Dems are running from the law.

The big picture remains the same: All that will really matter is whether the policy works over the long haul. But jittery Democrats are not in a big picture mood right now, and the new Quinnipiac poll finding Obama at his lowest approval rating ever is not going to make them any more inclined to take the long view. So they are telling the White House in no uncertain terms that a fix is a must, and fast.