AUGUSTA, Maine (AP) Money is pouring into the campaign battle over a $1 billion hydropower transmission project in western Maine.

Project supporters outspent opponents more than 2 to 1 in the latest reporting period. Financial disclosures filed Monday indicate that Central Maine Power-backed Clean Energy Matters spent nearly $4.5 million and Mainers for Local Power spent more than $2 million.

Critics who say the project would permanently change the character of the western Maine woods collected enough signatures for a referendum on the project.

Supporters say the project would reduce carbon pollution and lower utility prices across the region.