(CNN) Health care is dominating the 2018 midterm elections.
In nearly every competitive Senate, House and governor's race, Democrats are turning the issue into the focal point of their television advertising campaigns, debate strategies and stump speeches.
As a result, Republicans are having to adjust to a shifting political reality: Voters have traditionally punished the party that seeks to change the nation's health laws. For nearly a decade, that meant Democrats spent every election cycle under attack. Now, Republicans who called for the repeal of President Barack Obama's health care law -- which features some popular elements, like protections for those with pre-existing conditions -- are on the defensive.
For many GOP candidates, it's the first time they've been forced to answer for their own histories and propose their own solutions.
The American public has swung drastically in Democrats' favor on Obamacare. At this point four years ago, 48% of registered voters felt the law went too far -- but now, that's down to 36%, a new Fox News poll found. Meanwhile, a majority think it's either about right (21%) or didn't go far enough (30%). And 64% of registered voters want to see more people insured, even if doing so costs the government more money.
Seizing on the political opening, Democrats have spent nearly $125 million on TV ads focused on health care this year, compared to just $50 million in health care-focused ads from Republicans, according to the political ad tracking firm Kantar Media/CMAG.
The pressure has left some GOP candidates spinning -- insisting that they would defend pre-existing conditions protections and lower health care costs without detailing exactly how they'd do that.
Even Republicans who haven't voted to repeal Obamacare or sued to block portions of it are under fire over health care.
In Indiana, the home to one of the most competitive races for US Senate, Republican challenger Mike Braun is airing television ads touting the health coverage offered by his own business, where he says insurance premiums have remained flat for 10 years.
But a closer look at his business casts doubt on whether a Braun-style plan would be a better deal for most Americans.
What Braun doesn't say in his ads: His company's insurance plan features a deductible of $5,000 per year for individuals and $10,000 per year for families, according to the employee handbook of Braun's auto-parts business, Meyer Distributing, obtained by CNN. High deductibles are one of Americans' chief health care complaints and are a top target for Republicans' attacks on Obamacare.
The average deductible nationally is $1,500 for single plans, according to the Kaiser Family Foundation. That means Braun's company's workers who get sick could face steeper-than-average medical bills. High deductibles are also a way to keep premiums in check. Meyer's employee handbook shows that workers pay $34.30 biweekly in premiums for themselves or $198.44 for a family. Compared to national averages, that's about $300 cheaper for the year for single workers and $550 cheaper for those whose plans cover their families in 2017, according to Kaiser. The company did not respond to a request for comment on its health insurance plans.
Democratic Sen. Joe Donnelly's campaign says the high-deductible plan undercuts Braun's argument that he has better solutions to rising health insurance costs.
"Even his overhyped health care plan for his own employees is only a 'solution' if they're as wealthy as he is," Donnelly spokesman Will Baskin-Gerwitz said.
And Braun's campaign answered questions about his company's health care plan with an attack on Donnelly.
"While Hoosier premiums doubled and all but two insurers fled Indiana on Senator Donnelly's watch, Mike Braun delivered solutions by taking on the insurance companies, holding premiums steady for 10 years running and covering pre-existing conditions before it was cool," said Braun spokesman Josh Kelley.
One of the most dramatic midterm makeovers is happening in Texas, where Sen. Ted Cruz -- the man who once played a leading role in a 2013 government shutdown against his own party's wishes in a failed bid to repeal Obamacare -- is now defending one of its core elements.
Cruz campaigned for president in 2016 on the promise to repeal "every single word" of Obamacare. In early 2017, Cruz argued that Congress should repeal Obamacare immediately, and then work out a new version of health reform afterward.
Now, he says, there's one part of Obamacare he wouldn't roll back.
"You need to understand, everyone agrees we're going to protect pre-existing conditions," Cruz said while lambasting Obamacare for increasing insurance premiums during a debate last week.
Cruz touted his "Consumer Freedom Amendment," introduced last year, which he said would have protected those with pre-existing conditions. But the bill would have created parallel markets, with insurers offering some plans that don't meet Obamacare's requirements and others that do. The prices of those that do meet the law's requirements would skyrocket, health care policy experts said at the time. Insurance companies lobbied against Cruz's proposal.
His Democratic challenger, Rep. Beto O'Rourke, said: "I don't know how you're going to repeal every single word of the Affordable Care Act and keep protections for pre-existing conditions."
In Missouri, Republican attorney general Josh Hawley -- who is challenging vulnerable Democratic Sen. Claire McCaskill -- attempted to address a growing political problem with a new television advertisement this week.
In the 30-second, straight-to-camera spot, Hawley says he and his wife learned their oldest son has a "rare chronic disease" earlier this year -- "a pre-existing condition. We know what that's like."
"I support forcing insurance companies to cover all pre-existing conditions," Hawley says in the ad.
However, Hawley is one of 20 Republican state officials who signed onto a federal lawsuit seeking to strike down former President Barack Obama's Affordable Care Act as unconstitutional. They are backed by President Donald Trump's Department of Justice, which would strike down the pre-existing conditions protections but not the whole law.
If they succeed, that would mean eliminating Obamacare's mandate that prevents insurers from denying coverage or charging higher premiums to the 52 million non-elderly adults with pre-existing conditions.
"Nerve," McCaskill tweeted in response to Hawley's ad. "He sues to wipe out the protection then 'goes to camera' to say he doesn't mean it. He knows there are zero protections for pre-existing conditions if his lawsuit is successful."
In a late bid to insulate Republicans on the issue, Nevada Sen. Dean Heller -- the most vulnerable GOP senator this year -- and nine other Republicans introduced a bill in August intended to keep protections for those with pre-existing conditions in place.
However, health care policy experts pointed out that while the bill would forbid insurers from rejecting or jacking up prices for those with pre-existing conditions, it would allow them to exclude coverage related to those conditions -- or base prices on factors like age, gender and occupation. And the bill hasn't stopped Heller's Democratic challenger, Rep. Jacky Rosen, from attacking him for voting in favor of the repeal effort.
Republicans have also tried to pivot away from the issue of pre-existing conditions by contrasting their positions with the growing Democratic support for single-payer health coverage.
In hammering the GOP over health care, the lawsuit could be the single most effective weapon Democrats have as November's midterm elections approach.
In at least eight gubernatorial races, Democratic candidates and their supporters have aired television ads focused on pre-existing conditions. They've used the lawsuit to target Ohio attorney general Mike DeWine, who signed onto the lawsuit and is running for governor. West Virginia attorney general Patrick Morrisey, who is challenging Democratic Sen. Joe Manchin, is another Republican who has signed onto the lawsuit.
In Wisconsin, Gov. Scott Walker's Democratic challenger, state education chief Tony Evers, last week challenged Walker to drop out of the lawsuit. In a show of how complicated the politics are for Republicans, Walker has backed the lawsuit but promised he would call a special session of the state legislature to pass a law requiring coverage for pre-existing conditions if the lawsuit is successful.
The Democratic attacks also involve previous lawsuits -- like those Michigan attorney general and gubernatorial hopeful Bill Schuette signed onto. Schuette, who promised for years to undo Obama's signature law, has this year insisted he wants to protect those with pre-existing conditions.
And they've focused on years' worth of GOP votes to repeal Obamacare.
In Florida, on Tuesday Democratic gubernatorial candidate Andrew Gillum released a new ad bashing his GOP opponent, former Rep. Ron DeSantis, for voting to repeal Obamacare, charging that "DeSantis demanded that any new health law eliminate protections for people with pre-existing conditions." DeSantis responded by highlighting Gillum's calls for single-payer "Medicare for all," saying that Gillum is running on a plan "that would abolish private health care for millions of Floridians."
But, like in Indiana, Democrats haven't needed their Republican foes to sign onto the lawsuit or vote to repeal Obamacare to make health care their focal point.
In Montana, Democratic Sen. Jon Tester's supporters are lambasting his GOP challenger Matt Rosendale, the state auditor, for green-lighting insurance companies' plans for rate hikes and for hiring an insurance industry lobbyist as his deputy insurance commissioner.
Rosendale responded by tweeting that the Tester camp's claims were "LIES!!!" and that he is "going to protect Montanans with pre-existing conditions and deliver health care WE CAN ALL AFFORD!!!"