Centrist

In politics, centrism usually refers to the political ideal of promoting moderate policies which land in the middle ground between different political extremes. Most commonly, this is visualized as part of the one-dimensional political spectrum of Left-Right politics, with centrism landing in the middle between left-wing politics and right-wing politics. However, there is arguably more than one dimension to politics, so even the centre has its own radicals as exemplified by radical centrist politics.

FROM: http://en.wikipedia.org/wiki/Centrist