To say the least. Preexisting conditions and the ability to access and keep health insurance is one of the most, if not the most, critical issues on Tuesday. It may be the most important provision of the Affordable Care Act. The ACA, however, and other protection for preexisting conditions that came before it, could be in jeopardy.

Let’s define a preexisting condition. Preexisting conditions are ongoing medical issues that predate health insurance enrollment. There is no specific definition, so insurance companies can delineate what constitutes a preexisting condition. Certainly serious conditions such as cancer and heart disease qualify, but some insurers have also characterized pregnancy as a preexisting condition.

Protection depends on what and/or where you get your health insurance. Medicare and Medicaid don’t discriminate in coverage or price on the basis of preexisting conditions. A majority of working people–approximately 80%–get their coverage at work. The protection offered by HIPAA, the Health Insurance Portability and Accountability Act enacted in 1996, enables individuals (and family members) with preexisting conditions to change jobs without risking the loss of health insurance. They must continue to maintain coverage for more than 63 days in order to eliminate any waiting period for enrollment. HIPAA was not as successful, however, at safeguarding individuals without employer sponsored health insurance, and even those with preexisting conditions and continuous coverage often find policies unaffordable.

Without the ACA, the strength of the prohibition of denying individuals with preexisting conditions health insurance could fade away. HIPAA protection was incorporated into the ACA, so striking the ACA down may render HIPAA moot. Although many Republicans strenuously insist that they won’t eliminate the preexisting conditions regulations, the repeated attempts to repeal the ACA says otherwise. And proposals introduced by Republicans in Congress don’t come close to replicating the preexisting coverage put forth in the ACA.

We’ll all see what happens.