One way to solve it was as follows. Start by solving for the Constitution party:
Democrat * 3 = Libertarian
Reform * 3 = Democrat
Libertarian/Constitution = Reform
so...
Reform * 9 = Libertarian
Constitution = (Reform * 9)/Reform
Constitution = 9
Since all answers have to be integers < 50, the possibilities for Libertarian/Democrat/Reform are:
Libertarian = 9, Democrat = 3, Reform = 1
Libertarian = 18, Democrat = 6, Reform = 2
Libertarian = 27, Democrat = 9, Reform = 3
Libertarian = 36, Democrat = 12, Reform = 4
Libertarian = 45, Democrat = 15, Reform = 5
We can solve for Green in terms of Democrat:
Green - 9 = Puzzle
Green = Republican + Democrat
Puzzle2 = Green * Republican
(Green - 9)2 = Green * (Green - Democrat)
Green2 - 18*Green + 81 = Green2 - Democrat*Green
(18-Democrat)*Green = 81
So the possibilities for Green are:
if Democrat = 3, Green = 5.4
if Democrat = 6, Green = 6.75
if Democrat = 9, Green = 9
if Democrat = 12, Green = 13.5
if Democrat = 15, Green = 27
Only the last possibility is valid, so...
Constitution = 9, Libertarian = 45, Democrat = 15, Reform = 5, Green = 27, Republican = 12, and Puzzle = 18.