DENVER — Gov. Jared Polis joined the launch of a campaign urging voters to approve a November ballot measure that would let the state keep future excess tax revenue to spend it on schools and roads.

Polis joined Democratic House Speaker KC Becker and others Wednesday to launch the “Yes on CC” campaign, named after the ballot question drawn up by the Democrat-led Legislature.

It asks if the state can keep revenue that would otherwise be refunded under the Taxpayer’s Bill of Rights. The money would go to K-12 schools, higher education and transportation.

TABOR sets annual income limits that can trigger tax refunds. It requires voter approval for tax hikes.

Proposition CC’s critics claim TABOR limits the growth of state government.