PORTLAND – The state’s voters on Tuesday approved a constitutional amendment to change the timing of reapportionment of congressional and other political districts so Maine will be in sync with the rest of the nation.

The proposed amendment won with about 53 percent of the vote in unofficial returns reported Tuesday night. There was little public discussion and no active campaigning for or against the proposal since it was passed by the Legislature earlier this year and sent to voters for ratification.

Largely a housekeeping measure, the proposal seeks to shift reapportionment of congressional, legislative and county commissioner districts after 2013, moving the year from 2023 to 2021. Redistricting would then occur every 10 years after 2021.

In addition, the amendment requires a two-thirds legislative vote for reapportionment plans to be approved. In effect, it enshrines in the Maine Constitution a requirement already in state statutes.

While the proposal barely drew public attention before Tuesday’s balloting, the two-thirds requirement may have had a familiar ring to Mainers.

When congressional district lines were redrawn this summer and early fall, Republicans threatened to use their legislative majority to force through a reapportionment plan they favored, bypassing a statutory requirement of a two-thirds majority. In response, Democrats pointed to the proposed constitutional amendment and noted that eight of its 10 sponsors and co-sponsors were Republicans.

In the end, a compromise plan was agreed upon and the proposal won House and Senate passage with virtually no opposition.