Pertaining to politics, rather than the Extreme Left, or Extreme Right, the word Centrist implies middle of the road, moderate, as in “not going to extremes either way.”
In a country where people vote, the object is, the voters are either for or against certain issues, and for that reason, will vote for either one party, or the other.
For instance, those who believe that abortion offends the will of a god, will be voting for the party that promises to make abortion illegal. While those who want to give women the power to make their own decisions, will vote for the party that promises to keep abortion legal. When it pertains to the subject of abortion, there isn’t any middle of the road.
Gun control, or the lack thereof is another touchy subject, where voters either vote for one side, or the other side on that issue.
I suggest that politicians in the Centrist party, by trying to follow the middle of the road, will ultimately leave the middle of the road; veer off either to the extreme left, or to the extreme right, which has occurred to every group of politicians that tried to improve the old system for something new, and hopefully more agreeable to everyone.