Iowa Code § 49.89: Selection of officials to assist voters.

At, or before, the opening of the polls, the election board of each precinct shall select two members of the board, of different political parties in the case of any election in which candidates appear on the ballot under the heading of either of the political parties referred to in section 49.13, to assist voters who may be unable to cast their votes without assistance as described in section 49.90.