They probably want to push this now because who knows how much more difficult it may be if they have to start over again and maybe try to confirm a conservative after the election.
They have plenty of time to confirm a conservative before the election (especially if they keep with the rushed schedules), and they can even confirm a conservative AFTER the election but before the new Senators are seated (oh, we lost our majority in the election? so sad, let’s confirm!). And either way, pretty much every most likely Senate projection shows Republicans gaining seats this cycle, which will make confirmations even easier for the next two years.