Elizabeth Warren isn't the Democratic presidential front-runner. At least not yet.
But she's got enough momentum to draw increasing attacks from a range of rivals.
Mayor Pete Buttigieg went directly after Warren this week for avoiding answering questions about whether the single-payer insurance plan she supports would mean middle-class tax increases.
Joe Biden takes veiled shots at Warren for once being a Republican. And one of his high-profile supporters recently penned an op-ed calling her a hypocrite for touting a campaign fueled by small donors when she's previously taken money from typical deep-pocket sources.
The dynamics are new for Warren. They demonstrate her strength. But it also will test whether she can take the next steps to dispatch fellow progressive Bernie Sanders and overtake Biden for the nomination.