Politico: San Francisco billionaire Tom Steyer is giving Democrats a taste of the divisive, big-spending primary battles that have caused Republicans so much heartburn over the past four years.
And he says it's for their own good.
The former hedge fund trader-turned-philanthropist is bankrolling a far-flung political operation pushing environmental causes and candidates, including his pricey effort to torpedo the Keystone XL oil pipeline. He's increasingly drawing scrutiny for trying to take down the...