President Donald Trump answers questions during a meeting with military leaders in the Cabinet Room on October 23, 2018 in Washington, DC.

President Donald Trump promised again Wednesday to protect coverage for Americans with pre-existing conditions. His repeated pledges ahead of the Nov. 6 midterm elections mask the fact that his administration has backed efforts to undermine the popular Affordable Care Act provision.

On Wednesday morning, the president claimed that Republicans will "totally protect people" with pre-existing conditions, while "Democrats will not!" Trump's tweet was his second this month promising to fight for the protections. Democrats have hammered the GOP over the issue as they try to take a House majority in November's elections.

Trump tweet: Republicans will totally protect people with Pre-Existing Conditions, Democrats will not! Vote Republican.

The ACA bars insurance companies from charging customers more or denying them coverage if they have a health problem before their coverage begins. Even as Trump has publicly backed pre-existing condition coverage, his administration has helped to put the provision in jeopardy. The Justice Department decided not to defend Obamacare in court against a Republican-led lawsuit from 20 states challenging the health-care law's constitutionality.

They argue the full Affordable Care Act does not hold up legally after Republicans scrapped its core individual mandate provision as part of their tax law last year. By declining to defend Obamacare, the Trump administration tacitly supported the litigation, which could lead to the end of the pre-existing condition provision if the states win their lawsuit.

On Monday, his administration also moved to expand access to short-term health plans that may not necessarily cover pre-existing conditions. Health-care advocates also raised concerns that the House's Obamacare repeal plan — which all Democrats opposed as it narrowly passed the chamber last year with GOP support — could weaken the protections. Republicans never managed to repeal the law as the Senate failed to pass its own version of the bill.

Democrats have made health care their top messaging priority as they try to flip the House and numerous governor's offices around the country. Attacks over pre-existing conditions have put Republicans on the defensive. Now, numerous politicians who backed efforts to repeal and replace Obamacare are pledging their support for the provision, which about three-quarters of Americans support, according to a Kaiser Family Foundation survey.

Walker tweet

Even a U.S. Senate candidate who signed on to the lawsuit challenging Obamacare — Missouri's Republican attorney general, Josh Hawley — has promised to protect pre-existing condition coverage as he pushes to repeal the law.

It is unclear how Republicans would protect people with pre-existing conditions if they got rid of Obamacare. As Democrats hammer them over health care, GOP lawmakers have proposed bills to shield those patients.

But the proposals have possible loopholes that could jeopardize coverage, according to Politifact.

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