The next round is scheduled for May 22. They very possibly will never happen, but if they do, there is little reason to think that Hamas won't win again.
The latest poll that asked this question seems to be the September 2020 survey by the Palestinian Center for Policy and Survey Research. At that time, 34% said they would vote for Hamas and 38% for Fatah, with 20% undecided. (There have been no more recent polls on this topic from the other two major Palestinian polling centers, the JMCC and the PCPO.)
Things have changed since then.
In the past couple of days, a breakaway party from Fatah seems to have formed, led by Nasser Al-Kidwa, Yasser Arafat's nephew. Kidwa, who is a member of Fatah's Central Committee, is apparently upset at the anti-democratic methods being used to choose the Fatah slate, and he is enlisting other Fatah members as well as people from leftist organizations, followers of Abbas rival Mohamed Dahlan and possibly even supporters of imprisoned terrorist Marwan Barghouti to create this alternative slate.
Fatah is furious, threatening to expel from the party anyone who tries to run in elections without official approval from the party leaders.
Kidwa does not seem to have the charisma necessary to win an election. But even if he siphons off 20% of Fatah votes, that is enough to give Hamas a comfortable victory, without accounting for the undecideds from six months ago.
Hamas is also under attack for its own undemocratic methods of choosing a legislative slate, but unlike Fatah, it is strong enough to quash any serious opposition.
The world was shocked when Hamas won the last elections. If the May elections actually take place, it could easily happen again.