It's possible. The similarity is in the fact that Corbyn's base never believed that he would lose and refused to even entertain the possibility. You always have to acknowledge that losing is a possibility. Sanders being popular right now doesn't mean that barrage of GOP attack ads couldn't change that.
All that aside, Sanders is already saying that he would look at compromising with Republicans which could signal a shift to the center heading into the election. If Sanders is the nominee he is probably going to sound slightly less left than during the primary.
https://www.cnn.com/politics/live-news/cnn-02-06-20/h_0bf7b73baea014964fd9ead425f1e0d3Bernie Sanders said he – as president – would take the idea of compromising with Republicans on health care on a “case-by-case” basis, arguing that he could convince the American public to join him.