The arguments come at a difficult time for Republicans as they try to defend their control of the House and Senate in the November elections while many Democrats make health care a central issue in their campaigns. The court case will help them to put GOP candidates in competitive races on the defensive.

Supporting the lawsuit would put GOP candidates at odds with many voters who want pre-existing conditions covered, while opposing it would alienate conservatives who want the Democratic law undone.

Uniting Democrats

It may be a gift for Democrats, who enjoy an advantage on the handling of health care in surveys after repeated efforts by GOP lawmakers to repeal the 2010 law. Preserving the provision that guarantees coverage for pre-existing conditions unites Democrats across the political spectrum.

“The fact that this lawsuit is taking place in September means that the GOP's health-care agenda — the way they're trying to increase premiums and cut coverage for preexisting conditions — will be front and center for voters minds,” said David Bergstein, a spokesman for the Democratic Senatorial Campaign Committee.

A spokeswoman for the National Republican Senatorial Committee didn't return messages seeking comment.

To gain a House majority, Democrats need to flip 23 seats, a prospect that independent analysts say is within reach. The party will have a tougher time gaining two seats to control the Senate, where Democrats have 26 seats to defend, compared with just eight for Republicans.

The lawsuit has become an issue in the West Virginia Senate race, where incumbent Democrat Joe Manchin is in a tight race with Republican Patrick Morrisey in a state that Trump won in 2016. Manchin has aired a TV ad connecting Morrisey to the lawsuit, with testimonials from West Virginians with illnesses.

In another close Senate race in Missouri, the Democratic group Majority Forward is running a spot against Republican candidate Josh Hawley, for backing the Texas lawsuit as state attorney general. Hawley is challenging Senator Claire McCaskill in another state carried by Trump.

In the House, Democratic candidates in competitive races are highlighting support for pre-existing condition rules, including Aftab Pureval in Ohio and Josh Harder in California. Tyler Law, a spokesman for the Democratic Congressional Campaign Committee, said the party intends to highlight the lawsuit in competitive districts.

Health poll

An Aug. 23-28 survey released Wednesday by the nonpartisan Kaiser Family Foundation found that three in four Americans said it's “very important” that Obamacare's protections for pre-existing conditions remain law, including majorities of self-identified Democrats, Republicans and independents.

Yet some GOP strategists said the Democrats' strategy would backfire.

“It's a massive gamble on the part of the Democrats” to highlight the Affordable Care Act in Republican leaning states like Missouri, said Brad Todd, a GOP strategist with clients in House and Senate races. “It's going to blow up. Obamacare is still a winning issue for us.”

Todd said the Affordable Care Act's consumer protections may be popular but that full Affordable Care Act doesn't need to remain in place to preserve them. “Voters believe you can fix the preexisting condition protections and get rid of the rest of Obamacare,” he said.

Guy Cecil, who leads the Democratic super-political action committee Priorities USA, said the group will likely highlight the lawsuit in its upcoming ad campaigns aimed at winning seats in the election.

“Ever since Republicans came close to repealing the Affordable Car Act, health care has consistently ranked as a top issue in every survey and exit poll,” Cecil said in an email.

Staying quiet

But while Republican lawmakers sided with previous lawsuits that would have overturned or weakened Obamacare, many are neither endorsing nor denouncing this one. Senator Chuck Grassley, an Iowa Republican who is chairman of the Judiciary Committee, declined to say when asked if he supports the Texas suit.

The complaint alleges that the Affordable Care Act is unconstitutional after Congress last year zeroed out the tax penalty for not complying with the requirement to buy insurance. The challengers argue that because the individual mandate was a core component of the original law, the rest of it should be declared unconstitutional. The Wednesday arguments will be over the plaintiffs' motion for a preliminary injunction.

“The legal argument is clever, but ultimately baseless in principle and an extreme long-shot as a practical matter,” said Jonathan Adler, a law professor at Case Western Reserve University who helped craft a Republican-backed lawsuit that would've weakened Obamacare, but failed at the Supreme Court in 2015.

In an attempt at damage control, 10 Senate Republicans — including Nevada's Dean Heller, the most endangered GOP senator on the 2018 ballot — have offered legislation that would reinstate protections for pre-existing conditions if the lawsuit is successful. The bill contains carve-outs that would make those regulations weaker than they are under current law, said Larry Levitt, a health policy expert with the nonpartisan Kaiser Family Foundation.

“With the uncertainty of the outcome in the upcoming Texas v. United States case, this legislation is needed now more than ever to give Alaskans, and all Americans, the certainty they need that protections for those with pre-existing conditions will remain intact,” said Republican Senator Lisa Murkowski of Alaska, who voted against her party's push to repeal the Affordable Care Act.

Senator Susan Collins, a Maine Republican, said the legislation doesn't go far enough in protecting sick people because it fails to reinstate ACA rules that require a minimum package of benefits in most insurance policies.

The case is Texas v. U.S., 4:18-cv-00167, U.S. District Court, Northern District of Texas (Fort Worth).

— With assistance by Steven T. Dennis

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