Like it or not, Government is built on coalitions. If it weren't the Republicans and Democrats they would be called something else because the only way to coilate power in government is to join together with other groups that share your political viewpoint, although they don't neccessarily have to be in complete agreement on every issue.
What we are really hungstrung by is the influence of money on Congress. Money wins campaigns, and it's much easier for a corporation to donate a ton of money than it is for honest politicians to raise money through grass-roots methods.