Requiring employers to provide a retirement savings option or facilitate employee enrollment in a state plan (tax-deferred plans with multiple investment options)
Enrolling employees automatically, but allowing them to opt out
Ensuring employee contributions are portable between jobs and fully vested immediately
Making participation open to independent contractors as well as traditional employees
Advocating a change to federal law to allow state/local governments and employers to contribute to accounts (federal law must exempt state/local governments and employers from fiduciary responsibilities under ERISA when they contribute to these savings options); under such a change, states and municipalities could:

Contribute matching funds up to a certain amount or one-time/regular contributions of a fixed amount
Means test contributions
Use tax breaks to incentivize or require contributions to accounts from employers who are not otherwise contributing to their employees’ retirement