At the time, Latham was the 'messiah', and I'm assuming what you've read about the matter attempts to claim the opposite. That he offered nothing, and was destined to be a political failure. In fact I even recall that Alan Ramsay, who we all know passionately despised John Howard, stated, along with many others on the morning of the election, that Labor would be installed as Government.
In fact he even made the comment in retrospect "I always thought right up until the last week that there was a chance that Labor could win and I still believe irrespective that he was the best hope they had. Much better, far better than Crean and, I’ve got no doubt in my mind, far better than Beazley and who else was there? Nobody, but he had 12 months to sell a message that the other two had been trying to sell for eight years and had seen the Labor Party absolutely plummet and 12 months was too little by a bloke who was not well known across the community."
Unlike others, Ramsay did not alter his view following the election to suit his ends and attempt to rewrite the mood of the campaign.
You have to remember that polls scantly reflect what will happen on election day, and although 1998 was tight, it was of course fought on the GST.