Working with the polling firm YouGov, CBS News has been conducting a tracking poll of support for candidates for the Democratic 2020 presidential nomination in early-voting states. In other words, the pollsters go back to the states over and over to gauge support — and, in fact, they go back to the same prospective voters repeatedly. …
According to CBS’s Kabir Khanna, a quarter of Democratic likely voters changed the candidate they identified as their first pick over the past month. Warren was the biggest beneficiary of those changes, slicing away one-eighth of supporters from Sen. Bernie Sanders (I-Vt.), about the same percentage of support from South Bend, Ind., Mayor Pete Buttigieg and more than a fifth of those who’d previously backed Sen. Kamala D. Harris (D-Calif.). At the same time, Warren held more of her support than did any other candidate. CONT.
Philip Bump, Washington Post