Democrats weathered the government shutdown by standing united. And even as ObamaCare stumbled through a rocky rollout, Democratic lawmakers remained largely in sync with the administration even as they expressed disappointment about the flawed health exchange website.

Yet ObamaCare's flaws have proven to be far more serious than a few poorly written lines of software code. Lingering problems with the site, combined with fresh concerns about rising premiums and Americans being pushed off their existing health care plans, have further eroded the law's political standing, prompting congressional Democrats to begin putting more daylight between themselves and the White House.

To be sure, some congressional Democrats have been calling for changes to the law for a full month. When's glitches threatened to prevent millions of uninsured Americans from obtaining coverage in time to avoid the individual mandate's penalty, squishy Democrats suggested punting the deadline, a concession the White House ultimately made.

The latest criticisms are far more pointed though, focusing not only a technological screw-up, but on the president's very credibility.

Obama vowed that people who liked their existing health plans would be able to keep them under ObamaCare, though that claim has proven to be false. Sen. Mary Landrieu (D-La.) — who, notably, faces a tough re-election campaign next year — introduced a bill last week that would smooth over that politically perilous contradiction. Called the "Keeping the Affordable Care Act Promise Act" (zing!), the bill would allow people in the individual insurance market who meet certain criteria to keep their existing plans, even if those plans don't meet ObamaCare's rigorous new standards.

The bill attracted a couple of expected co-sponsors in Sens. Mark Pryor (Ark.) and Kay Hagan (N.C.), both of whom are also up for re-election in red/purple states next year. But it also curiously drew the backing of solidly blue state Democrats Sens. Dianne Feinstein (Calif.) and Jeff Merkley (Ore.), indicating that critiques of the law are no longer limited to anxious swing-staters with an eye on 2014. Rather, Democrats from the left, too, are feeling the pressure to fix the law — and soon.

A private meeting between the White House and House Democrats Wednesday "became heated when rank-and-file members expressed frustration about continued ObamaCare problems," according to CNN's Dana Bash. Several lawmakers reportedly demanded the administration come up with its own solution to the problem of people losing coverage before Friday, when the House will vote on a Republican plan crafted by Rep. Fred Upton (Mich.) that would do just that.

Upton's proposal would grandfather in existing plans that would otherwise be nixed by ObamaCare. But it would also, unlike Landrieu's bill, let new enrollees keep signing up for those same plans, a sticking point with many Democrats, since the old plans often did not provide adequate coverage.

The testy meeting came one day after Bill Clinton said Obama "should honor the commitment the federal government made to these people [who have lost their old plans] and let them keep what they got." Coming from such a respected party leader, the remark "provided air cover for lawmakers to increase pressure on the White House to come up with a fix," wrote Politico. Emboldened by Clinton's harsh words, House Democrats "issued a stern warning to the administration officials: Fix it or face a full-scale rebellion."

ObamaCare's glaring failings have greatly eroded the president's standing with the American people, giving Democrats ample reason to back away from the president. A Quinnipiac poll Tuesday found that Obama's approval rating had dipped to an all-time low of 39 percent, and that for the first time in his presidency, a majority of voters said they didn't trust him.

That was before the White House revealed Wednesday evening that only 106,000 Americans had signed up for coverage under the health care law in October, well below the 500,000 figure administration officials had projected. The announcement came on the heels of a Washington Post report that claimed the administration was at risk of missing its own self-imposed deadline to have the health exchange website up and running smoothly by the end of the month.

Truly, it's been a terrible couple of weeks for ObamaCare, with bad headline after bad headline further undermining the wobbly health care law. Unless and until the administration can rectify the problems plaguing ObamaCare, congressional Democrats will only move further away from the White House, opening a wider rift between the two sides and threatening the law's long-term viability.