Money in politics, climate change, and gender are overtaking more traditional corporate governance concerns as top topics for shareholder advocacy in the U.S.

More than two-thirds of the proposals that pension funds, socially conscious investors, and others want to put to a vote at Russell 3000 companies this year cover environmental and social matters, rather than governance-related subjects such as executive pay, according to data collected so far by Institutional Shareholder Services Inc.

ISS, which gives institutional investors recommendations for...