You're asking about voter intentionality which is impossible to predict in any certain terms. If we know how voters would behave then we'd be able to hack democracy a long time ago.
If your question is: "How do I maximzie my chances of winning in IRV?" then that's at least answerable.
Taking examples from Australia's lower house election, it is very common for a candidate to only receive a plurality - but not majority - of votes on the first round. To maximize their chances of winning on subsequent rounds of counting, they have to persuade voters who did not vote for them to rank them on 2nd place.
To answer your question, your chance is already not bad if you know you have a plurality of votes secured on 1st round. Your task then is to understand where are you going to get the extra votes to push you over the majority threshold. In another word, among the candidates who will be eliminated after the first round, which one are you going to appeal to so that their supporters will rank you as 2nd on the ballot.
Not sure what you mean by "if abstaining votes aren’t counted" since abstaintion votes are never counted.