With his announcement on Thursday that his administration would allow insurers to delay non-Obamacare compliant policy cancellations for a year, President Obama hoped to regain control of the law's rollout ahead of a critical House vote later on Friday. Instead, he's seen increased media scrutiny, an empowered opposition, and tension with Democrats maintaining party-line discipline on a deeply contentious issue.

It's easy to assume, in our short-attention-span culture, that minor moments have major consequences. In this case, with the president's legacy-defining policy at stake, it seems clear that this month is his presidency's most important. Here's why.

Democrats have an incentive to buck the president.

On Friday, the House will vote on a proposal from Michigan Rep. Fred Upton that would codify a means of preventing insurance companies from canceling customer policies. It's a direct response to Obama's pledge that people could keep plans they like, and precisely what Obama hoped to undermine on Thursday. He's already pledged a veto of the policy, calling it a "brazen attempt to undermine or repeal the overall law." But the Upton bill is only one of three legislative fixes that have been proposed for the emerging issue of plan cancellations, as you can see at right, via ThinkProgress — each of which will force Capitol Hill Democrats to vote for or against the president.

Consider: If Upton's is the only measure that comes for a vote in the House, what is a Democrat running in a close race in 2014 going to do? Party leaders, according to Roll Call, have been meeting to figure out if there's a legislative response they can counter with. In the meantime, though, they're in a bind. "[F]earful of the political embarrassment of defections from the rank-and-file," Roll Call writes, "[leaders] wouldn't comment on whether they were launching a formal whip operation to urge 'no' votes on the Upton bill." In other words: Democratic leaders may let members vote with Upton — and against the president — for their own political good.

The Washington Post notes that the issue is just as difficult for Democrats on the Senate side. Louisiana Sen. Mary Landrieu, facing a tough re-election next year, didn't appear at an event with the president earlier this week — the sort of thing that is rarely unintentional — and has also introduced one of the legislative fixes listed above.

Obama hasn't done his party many favors on the cancellations issue. On Thursday, he apologized to Democrats who echoed his "if you like your plan, you can keep it line," which, the Post suggests, is already making things uncomfortable.

Rep. Nick J. Rahall II (W.Va.), a 19-term veteran targeted in 2014 by Republicans, said ads are running against him in his district based on the president’s promise to allow Americans to keep their health-care plans.

“I’m concerned about my integrity with voters that have returned me [for] 38 years. They know me enough to know I wouldn’t purposely mislead them and that I’m an honest, straight shooter,” he said. “They have that confidence in me, and I want to continue for them to have that confidence in me. I just need to find the answers myself.”

Both Obama's and Obamacare's popularity are sinking.

Rahall's point is reflected in the polling. As we noted on Thursday, the president's popularity and the popularity of Obamacare are at or near record lows. Opposition to Obamacare increased by 12 points over the course of a few weeks, thanks largely to negative news reports about the roll-out. Of more concern, as Obama's conservative critics eagerly point out, is that voters are losing confidence in the president's trustworthiness.

When Obamacare first passed, the president and his Democratic allies could at least fall back on the idea that the president's approval was high. Now, that's less and less the case. The public is less likely to want to support Obamacare, and less likely to care if Obama himself supports it.

His Republican opponents are gaining confidence.

On October 1, the government shut down as the Republicans unveiled a last-ditch attempt to undermine Obamacare by voting to defund the bill (for the 40th-plus time). But this month, after the stumbling roll-out of Healthcare.gov and the cancellations blowback, some Republicans think they could eventually have luck with a delay or repeal vote, as Buzzfeed's Kate Nocera writes.

Rep. Trey Radel laughed at a reporter when asked if he thought some in the conference might attempt to defund the law as part of the budget negotiations. When he stopped chuckling, Radel said that the president pushing to delay parts of the law on his own gives some validation to the Republican position.

For now, as we pointed out on Thursday, the Republicans hoping to stay out of the spotlight and let Obama and the Democrats stumble around in the public eye. But a month ago, a vote for delay or repeal of Obamacare seemed like an impossibility given a Democratic Senate and president. Now such a thing seems increasingly possible every day — and continued delays could, in theory, push implementation out long enough for there to be another occupant of the White House. This is deeply, deeply optimistic — but with Democrats appearing to waver, it's not a surprise that Republicans are feeling empowered.

Obamacare is being compared to the worst moments in other presidents' administrations.

The New York Times has a long story comparing the Obamacare roll-out and response to Bush's handling of Hurricane Katrina and its political aftermath. "The disastrous rollout of his health care law not only threatens the rest of his agenda," Michael D. Shear writes, "but also raises questions about his competence in the same way that the Bush administration’s botched response to Hurricane Katrina undermined any semblance of Republican efficiency."

As Talking Points Memo notes, there's some irony in the critiques in the Times, offered, as they were, by former Bush aides. Bush aides have been pushing the Katrina or Iraq metaphor for some time. And as Slate points out, it's not a great analogy anyway. But the reason the comparison is being made is, at least in some cases, with hopes that it will stick. (And in the case of the Bush staffers, to help burnish another president's legacy.)

Then there's Iran-Contra, the gun-selling scandal for which Reagan offered his apologies late in his second term. Obama supporter Andrew Sullivan favorably compared the president's apology on Thursday with Reagan's. Matthew Continetti at the conservative Free Beacon drew the same analogy, but cast a different light on Obama as a result: "a complicated and controversial policy dispute that involves deception, a hostile Congress, and the bludgeoning of presidential credibility."

Things were already going badly for the president.

As we've noted, there is a strong correlation between the economy and a president's approval rating. Obama's approval was dropping before the Obamacare problems in large part thanks to the still-slow economy. Concerns over the health care law have only compounded an already problematic situation.

Obama is also losing allies besides Democrats on Capitol Hill. The on-going NSA and privacy revelations have undercut his support, including in Silicon Valley. And his plan to allow a one-year delay in coverage cancellations launched a battle with insurance companies that, to date, had been largely helpful in the launch of the health care policy.

Things change quickly in politics, as we've seen over the last month. Friday's vote in the House will be a significant marker, but it will pass. The greater question is whether or not the political tension that's built over the past month and will continue over the short term will have a permanent negative affect on the implementation of Obamacare. If it does, as the National Journal's Ron Brownstein notes, it could prove to be a long-term drag on Democrats. For Obama, it could set his legacy in cement — and not the legacy he is hoping for.