Americans overwhelmingly say they'd vote for Democrats who support Obamacare over Republicans who want to repeal it.

Americans overwhelmingly trust Democrats over Republicans when it comes to health care — and that spells trouble for the GOP in November.

According to a new survey from Public Policy Polling, a large majority of voters (56 percent) say they would support a generic Democratic candidate for Congress who supports Obamacare, also known as the Affordable Care Act. Just 40 percent say they would support a generic Republican candidate who wants to repeal Obamacare.

For voters over the age of 65, that big 16-point gap grows even bigger, to 19 points (59 percent to 34 percent). Older Americans simply don’t want Republicans to mess with their health care.

An overwhelming majority of voters (59 to 34) also want Congress to “keep what works and fix what doesn’t” in Obamacare — not repeal it.

After years of trying to repeal Obamacare outright, followed by attempts to dismantle it through stealthier means, the GOP is now synonymous with undermining access to affordable health care.

Voters don’t like that one bit — and women voters and independent voters like it even less.

On “the issue of health care” generally, voters trust Democrats over Republicans and Trump by 13 points (55 to 42). That trust gap balloons to 26 points among women voters (60 to 34), and 22 points (57 to 35) among independent voters.

And only 19 percent of voters support the Trump administration’s efforts to get rid of Obamacare’s protections for people with pre-existing health conditions.

Twenty states are currently suing to invalidate one of Obamacare’s most important and popular guarantees: that no matter what pre-existing health conditions a person has, from acne to cancer, that person cannot be denied health coverage or get charged a higher rate by insurers.

The Trump administration has thrown its support behind this dangerous lawsuit.

If the Trump-backed lawsuit is successful, insurance companies would once again be able to overcharge or deny coverage to the 52 million American adults under the age of 65 who have pre-existing conditions.

As Americans turn against the GOP’s health care attacks, Democrats are making the defense of Obamacare a defining issue in the 2018 midterm elections.

And Congress isn’t the only fight that could turn on health care. The issue will also be pivotal in the fight to block Trump’s extremist Supreme Court nominee, Brett Kavanaugh.

As a D.C. Circuit appeals judge in 2011, Kavanaugh weighed in against Obamacare by dissenting from a ruling that upheld the law.

This new poll shows just how vulnerable Republicans really are on health care — and just how much Democrats have to gain from defending it.