Support for President Obama's health care law has dropped 16 points in the past month -- and that's just among Democrats.

The finding, from a CBS News poll, is one of several startling numbers from polls released in recent days showing rapidly eroding public support for Obama's signature legislative accomplishment in the wake of its botched rollout.

Some highlights from the CBS poll:

— Just 58 percent of Democrats now approve of Obamacare, which is down from 74 percent in the same poll taken in October. Independents now oppose the law 67 percent to 27 percent. Last month, disapproval among independents was a much narrower 55 percent to 38 percent.

— Just 11 percent of those surveyed said the signup process for Obamacare’s health exchanges is going well.

— An even lower number (7 percent!) of those surveyed said Obamacare “is working well and should be kept in place as is.” In comparison, 48 percent said it needs at least some changes and 43 percent favor full repeal.

And from Tuesday's Washington Post-ABC poll:

— Americans aged 18 to 39 (a key demographic in Obama’s presidential election victories), now oppose the law by a 59 percent to 38 percent margin. Under the law, many younger and healthier Americans are being expected to pay more for insurance to help offset the costs to insurers of covering older and sicker enrollees, particularly those with pre-existing conditions.

— Among Americans with an annual household income of less than $50,000 (the income group that’s supposed to benefit most from the law), disapproval outweighs approval 59 percent to 38 percent.

With the 2014 midterm elections now in the horizon, what’s most striking is how closely Obamacare polling is starting to resemble polling on Iraq in fall 2006, when a public backlash against the war enabled the Democrats to take over control of both chambers of Congress.

A Gallup poll taken days before the Nov. 7, 2006, election found that 55 percent of Americans had come to view sending troops to Iraq as a mistake, compared to 40 percent who said it was not.

Yet in the CBS News poll released Wednesday, 61 percent of Americans were found to disapprove of Obamacare, compared to 31 percent who approve. In the Washington Post poll, the numbers were 57 percent to 40 percent.

Granted, asking whether people approve or disapprove of a policy might yield different results than asking whether they think a policy is a mistake.

But in answer to another question asking whether Americans approve of Obama's handling of the implementation of the health care law, the Washington Post poll found that 63 percent of Americans disapproved compared with 33 percent who approved.

A Time poll taken before the 2006 election found 65 percent disapproved of President Bush's handling of Iraq compared to 31 percent who approved.

To be sure, there's still nearly a year before the 2014 elections, so there's time for public attitudes of Obamacare to change. But it's no surprise that vulnerable Democrats are starting to get nervous.