It's interesting to look at the charts for the period. Gillard becoming PM resulted in the shocking Labor polls reverting to close to 50-50, even after the CT and Mining tax.
There was a huge blip for Rudd when he regained the PMship, which quickly reversed, but the trend was towards ALP.
Notice the figures around the 2013 election - it was a landslide. If there had been an election anywhere in 2014 or most of 2015, Labor would have had a landslide of unprecedented proportions.
IMO if the 2014 budget had been handled a lot better, and he had been straight with the electorate, Abbott might have had a chance of surviving and taking the LNP to a win.
http://www.roymorgan.com/findings/6831-morgan-poll-federal-voting-intention-may-30-2016-201605300615
