As Republicans on the campaign trail have contorted the truth about their monthslong campaign to undo the 2010 health care law, they’ve provoked a tricky opponent: cancer survivors.

Republicans have tried to contain the damage of their “repeal and replace” push as they defend their majorities in the midterm elections. In order to pull that off, the campaigns have had to find ways to discredit the sympathetic voices of people with complex medical needs who opposed their votes.

These health care advocates include people who got engaged in advocacy for the first time because of Republicans’ attempts to dismantle the law. They are patients with serious health conditions who are covered through the law’s marketplaces and patients who rely on Medicaid. They worry that without the law they could go into bankruptcy or go without care.

Republicans point to their support for state insurance pools as a source for coverage for high-risk patients, and more recent legislation that would ensure that people with pre-existing conditions can secure coverage, even if insurers wouldn’t necessarily cover care for those conditions. But the advocates aren’t buying it.

Their voices have been amplified by viral videos, by campaign ads and by organizations like Indivisible and Protect Our Care, an issue advocacy group that aligns with Democrats.