I don't think abortion is under threat from RM - he's made his Catholic views very clear but equally has said he would think it wrong to impose those views on others.
I know, I know, his voting record. IMO these votes were made to appease his Catholic conscience safe in the knowledge that there was no actual chance of a change in legislation. See also: gay marriage.
I think that in the outside chance he were to be in a position of power, he could actually serve as a really interesting example of tolerance. Something the left needs to learn asap.
Whatever your political leanings, he is clearly a bright man. He knows that access to abortion is essential to the well being of our society.
Although I do think that as the political right rises there will be much more anti abortion discourse. This is not necessarily bad. It's a serious topic and discussion is good.
I do not believe at all that access to abortion is under threat.