WASHINGTON -- No flood of people trying to sign up is expected for the start this weekend of open enrollment for health insurance through the federal and state run exchanges. The exchanges, created under the Affordable Care Act, are in their second year and unlikely to see the large uptick in enrollment that was once anticipated.

The lower estimates ahead of open enrollment Saturday are sure to play a role in the continued fight between Republicans and the White House over the law. The law is under assault on multiple fronts.

Congressional Republicans, empowered by winning control of the Senate in last week’s election, have made repealing ACA one of their top priorities. As long as President Barack Obama is in office they will not succeed, since he’ll veto any effort to eliminate his signature legislative accomplishment.

His administration will also have to defend the law in court -- again. The Supreme Court has agreed to hear a challenge that could eliminate subsidies for those people who bought insurance through the federal government because their states opted not to create exchanges. If the court strikes down the subsidies, millions already enrolled in the exchanges may not be able to continue to afford coverage. 

And when enrollment opens Saturday, the White House (and would-be enrollees) will have to hope the technical problems that plagued last year's process have been fixed. 

The number of individuals enrolled through the exchanges is likely to play a role in discussions by Republicans about how to repeal the law. Mitch McConnell, who is expected to become Senate majority leader in January, said during his campaign the law should be repealed “root and branch.” Killing the entire law at this point would affect all those getting their insurance through the exchanges. The larger the enrollment becomes, the more difficult it is for the law to be undone. If enrollment is stagnant or perceived to be on the decline, Republicans may have an easier time making the case against the exchanges with little harm.

Republicans have admitted, at least privately, once the exchanges opened last year it would be more difficult for them to shut them down

The move Monday by Health and Human Services to set a low bar for success in the next round of enrollment could be an effort to stave off what would be sure criticism from Republicans if the number of new enrollees is lackluster.

HHS officials said Monday they anticipate 9 million to 9.9 million people will be enrolled in insurance plans through the exchanges by the end of the year, according to the Washington Post. That is a lower estimate than previous guesses, including from the Congressional Budget Office earlier this year, which estimated 13 million would be enrolled.

It’s not a decrease from the current enrollment, which officials said is about 7.1 million people. That’s a drop off from the 8 million who initially enrolled last year because some of them didn’t pay their premiums and 112,000 were dropped because they couldn’t prove they had legitimate immigration status.

The administration is explaining the revision in estimates isn’t a sign of problems with the law but merely the normal ramp-up of any new program. They pointed to Medicare Part D enrollment, which saw a large gain after eligibility was increased in 2006 but then leveled off quickly with only small gains each year.