U.S. Sen. Susan Collins. Credit: Linda Coan O’Kresik

U.S. Sen. Susan Collins said on Sunday that she is confident that a federal judge’s ruling declaring the Affordable Care Act unconstitutional will be overturned.

“There’s no reason why the individual mandate provision can’t be struck down and keep all the good provisions of the Affordable Care Act,” Collins told CNN’s Jake Tapper on “State of the Union.”

Her remarks come on the heels of last Friday’s decision by U.S. District Judge Reed O’Connor in Texas that the 2010 health care law is unconstitutional because of the repeal of its individual mandate as part of last year’s tax overhaul bill.

The lawsuit, initiated by Texas Attorney General Ken Paxton, argued that the health care law was invalid because the repeal of the mandate that all Americans have health insurance or pay a penalty has stripped the Affordable Care Act, also known as Obamacare, of its enforcement mechanism, according to the Washington Post. Gov. Paul LePage signed onto that lawsuit as an individual because he can’t represent the state in lawsuits without permission from the Maine attorney general.

[Judge’s ruling on Obamacare poses new problems for Republicans]

That lawsuit cited a 2012 U.S. Supreme Court decision that upheld the mandate as being within Congress’ taxation power, saying that the law can’t be severed from the tax.

In his 55-page opinion, O’Connor agreed, writing that the individual mandate is unconstitutional and “can no longer be fairly read as an exercise of Congress’ tax power.”

O’Connor’s ruling, which was issued just ahead of Saturday’s deadline to sign up for insurance under the health care law, isn’t expected to have an immediate impact on the Affordable Care Act, according to the Associated Press. His ruling is likely to be appealed, possibly up to the Supreme Court, which has twice — in 2012 and 2015 — upheld the Affordable Care Act.

“This isn’t going to affect people currently enrolled in Obamacare policies for 2019,” Collins said on CNN.

Collins cast a decisive vote last December to pass the Republican tax bill that repealed the individual mandate. Collins’ support for the bill came after pledges from Senate Majority Leader Mitch McConnell to support two measures to shore up the health care marketplace by restarting health care payments to insurers halted by President Donald Trump and providing $10 billion in reinsurance funds to help states cover the cost of care for the sickest patients. Those measures were ultimately delayed and not included in an omnibus spending bill passed by Congress in March.

[ACA signups in Maine appear to be down significantly]

Collins, who last summer voted against a Republican-led effort to repeal the Affordable Care Act, defended her vote to repeal the individual mandate under the tax bill, calling the provision deeply “unpopular.”

“There is widespread support for protecting people with pre-existing conditions, and there’s widespread opposition to the individual mandate,” Collins said.

Collins said on CNN that the mandate’s penalty predominantly fell on lower- and middle-income taxpayers, with 80 percent of those who paid the penalty making less than $50,000 per year. IRS data show that cohort accounted for 58 percent of total penalty payments.

Advocates who fought against the mandate’s repeal last year pointed to a 2017 Congressional Budget Office analysis that forecast that the mandate’s repeal would result in 13 million more uninsured Americans over the next decade and 10 percent increases in premiums most years over that timespan.