Currently, 21 U.S. states have some form of non-partisan or bipartisan redistricting commission. Of these 21 states, 13 use redistricting commissions to exclusively draw electoral district boundaries (see below). ;Table key For purposes of these tables: •
Bipartisan means a substantial majority of the commission's membership is reserved for members of the two major U.S. political parties. •
Non-partisan means that either, a) the partisan makeup of the commission is not specified beforehand, or b) a substantial portion (i.e. more than one) of the membership of the commission is reserved for
political independents or members of so-called
third parties. Iowa is a special case: Additionally, Maine and Vermont use advisory committees for redistricting. Connecticut, Illinois, Mississippi, Oklahoma, and Texas have backup redistricting commissions, if efforts at redistricting via the usual legislative process fail. ==2021 redistricting==