She indeed used to be Australia's Prime Minister. The Nationals are a much broader party, but also a bit more populist. Think of Hanson's One Nation mixed with the Nationals, with none of the moderating influence of the Liberals.
The racial makeup is similar, but with the notable exception of less people of Chinese descent. Instead, there are many more refugees from Southern Africa, both black and white.
It's similar to Tony Abbott. But not quite. While Abbott had to deal with the suburban/urban members of the Liberal Party, the Liberals in Australia are pretty much just relegated to the third wheel, contesting mostly against Labor in the cities. They are very much seen as a more cosmopolitan, moderate party of the old "cut taxes, business is great, who cares about social issues?" The Nationals, however, are very much One Nation, Populist, Socially Conservative, but fiscally protectionist with strains of rural socialism. This is what keeps them afloat as more than just a regional party. Australia's political landscape is different in this regard and actually a bit more dynamic than we would know it as.