In the upcoming election, several states intend to put abortion rights on the ballot for consideration by the voters with successful passage resulting in an amendment to that state's constitution which will preserve those rights.
Some candidates for Congress have indicated that if they are able to successfully take back both Congress and the Presidency, they would ban abortions on the federal level. For the sake of this argument, let's assume they have the votes to do so.
Presumably, the passage of a federal law to ban abortion nationwide would be in direct contradiction with state laws. However, if these various votes are successful this is a bit more than a state law, rather it's an amendment to a state's constitution. Would the passage of a federal abortion ban automatically repeal the various states' constitutional amendments? Or would they be considered void until such time that the federal law is repealed?
Could doctors in those states continue to perform abortions under the presumption that nobody in the state will enforce the federal law? This would be akin to how many states have legalized cannabis to a variety of degrees despite it continuing to be illegal on a federal level.