“Hardship” was precisely the word Health and Human Services Secretary Kathleen Sebelius invoked late last week in assuring six Democratic senators that — no — she wouldn’t punish those 6 million Americans who have lost their insurance because of Obamacare. The tax penalty won’t apply if they go without insurance or buy stripped-down catastrophic plans.

This was the latest in a string of moves to ease the pain of reengineering one-sixth of the nation’s economy. With the calamitous website rollout, deadlines have been eased and insurance companies “strongly” encouraged to accept late payments. And months before Healthcare.gov became fodder for comedians and commentators alike, the White House had granted a one-year delay in the employer mandate — after business leaders offered up their own hardship claims.

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Here’s why the White House’s desperate attempts to stem the political bleed may not be enough to hold onto the Senate:

1. Democratic control of the Senate hinges on the fate of seven Senate seats in states that rejected President Obama in favor of Mitt Romney in 2012. Ads that highlight Obama’s broken promises, repeated often by the Democrats — “if you like your insurance you can keep it; if you like your doctor you can keep him” — will prove powerful motivators against Democratic senators seeking to hold onto their seats.
2. While Democratic senators will be weighed down by the President’s Obamacare-driven low approval ratings and growing credibility gap, there’s another powerful political factor at work: People vote on things that directly affect their lives. Fear and anxiety over economic security — and health — is a much bigger motivator than, say, government deficits. So when millions of Americans start losing their health insurance or are being forced to pay higher premiums, a nervousness seeps into the body politic that is difficult to reverse.
3. Democrats can’t change the conversation to GOP “extremism.” The Pierre wing of the Republican Party failed to mount a repeat of its September-October political death march, when a government shutdown left the GOP with historically low approval ratings. This time the staunchly conservative — but politically astute — Paul Ryan, chair of the House Budget Committee, crafted a budget compromise with liberal Senate Democrat and budget chair Patty Murray. The deal passed, and the government stayed open. The result? At least right now, there is nothing to blur the narrative about traumas wrought by the President’s massive health care reform.
4. Even with a boost in enrollment figures, serious trouble threatens the Obamacare horizon. There is the real prospect that when open enrollment comes around next summer, employers will start canceling employee health insurance — preferring to pay the penalty rather than cover the cost of plans with Obamacare-required standards. And the greatest danger to Obamacare itself is the imbalance in enrollees. An older, sicker population is signing up. Younger, healthier customers — who make the economics viable — have stayed away, turned off by website problems as well as concerns about the security of their personal information. Will the White House be forced into a taxpayer-subsidy of insurance companies to keep the whole thing afloat? Will premium costs rise to keep the whole thing afloat? Talk about political dynamite.
5. Attempts by White House allies to boost the enrollment figures among a younger, healthier population don’t do much to give confidence to Democrats in swing states whose political futures are tied to the success (or failure) of the President’s health care law. The “Pajama Boy” tweet — featuring a twentysomething in a onesie next to text reading “Wear pajamas. Drink hot chocolate. Talk about getting health insurance” — went viral — but not because it was an effective outreach to uninsured adults. It drew a mass audience, including Obama allies, that was mocking its silliness.

And that wasn’t the only ham-handed attempt to boost enrollment. This week the Log Cabin Republicans denounced as offensive a lascivious ad targeting the gay community that featured men prancing around with each other in their underwear.

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To truly appreciate the uneasiness among Senate Democrats, it pays to listen to West Virginia Senator Joe Manchin, among the most outspoken Democrats calling for a delay in the health care law. Manchin worried out loud on CNN’s State of the Union last Sunday that the whole health care law could be headed for a “complete meltdown” if “it’s so much more expensive than what we anticipated, and if the coverage is not as good as what we’ve had.”

And the political victims? His Democratic colleagues up for re-election — and Obama’s control of the U.S. Senate.