In June, I wrote a column asking if Sen. Elizabeth Warren, who was starting to pick up steam after a disappointing debut in early 2019, could continue her rise up the ranks of the 2020 Democratic contenders. The answer to that, clearly, is yes. The next question is what it will take for her to win the nomination?

1. Can she grow her base?

Vice President Biden remains the solid favorite among older voters, African-Americans and moderate to conservative Democrats. Sen. Bernie Sanders is still the leading candidate among younger voters. Since August, Warren has made some small inroads into those demographic groups, according to CNN polling. For example, Warren gained 9 points among those over 45-years-old, while both Biden and Sanders lost ground (Biden lost four points, Sanders lost three). But, among non-white voters (Biden's core), Warren slipped two points and among 18-49-year-olds (Sanders voters), she gained just one point.

2. How will she respond to increased scrutiny?

Warren is not the frontrunner, but she's likely to be treated like one by the media, debate moderators and her opponents. What we do know is that she has (for now) endured what many thought would be a candidacy-ending controversy over her decision to take a DNA test to prove her Native American ancestry. While Trump still mocks the Massachusetts senator as Pocahontas, the issue no longer dominates the narrative about her as it did earlier this year. Her public apology at a forum of Native Americans this summer in Iowa was well-received by the members of that community, dampening any potential for the controversy to once again flare up. Maybe this issue has played itself out. But, we also can't say that for sure.

Meanwhile, her Democratic opponents are also starting to take aim at her. We saw this in the most recent ABC News debate when Sen. Amy Klobuchar, Joe Biden and South Bend Mayor Pete Buttigieg all explicitly criticized Warren's Medicare for All plan for its potential to raise taxes on the middle class and for kicking millions off of their private insurance.

Warren was able to evade specific answers to the question of how the plan would be paid for without raising taxes on average Americans. It's not clear that she can get away with that for much longer.

This week, Buttigieg continued to criticize Warren's health care plan. In an op-ed outlining his released his own health care plan, Medicare for All Who Want It, he wrote: "[T] here's a real difference between the plan I'm announcing on Thursday and the ones offered by candidates such as Sens. Bernie Sanders (I-Vt.) and Elizabeth Warren (Mass.)," Buttigieg writes. "Rather than flipping a switch and kicking almost 160 million Americans off their private insurance, including 20 million seniors already choosing private plans within Medicare, my plan lets Americans keep a private plan if they want to."

And, in an interview with CNN's Jake Tapper on Thursday, Buttigieg kept up the heat on Warren:

You know, Senator Warren is known for being straightforward, and was extremely evasive when asked that question [on how to pay for her Medicare for All plan].

And we have seen that repeatedly. I think that, if you are proud of your plan, and it's the right plan, you should defend it in straightforward terms.

And I think it's puzzling that, when everybody knows the answer to that question of whether her plan and Senator Sanders' plan will raise middle-class taxes is yes, why you wouldn't just say though -- so, and then explain why you think that's the better way forward.

Our plan does not require raising middle-class taxes. It does create a way for everybody to be covered. And I think that's what most Americans want.

3. Can crowd size help her?

Over the last few weeks, Warren has shown an ability to attract big audiences across the country, including a 20,000 person rally in New York City on Wednesday night. Crowd size doesn't equal vote share. There are a lot of people who show up to these events who are not going to vote for Warren. Or, maybe they aren't registered or even eligible to vote. But, perception matters too. And, images of Warren standing in front of a sea of people signals to voters that she is someone to pay attention to. Furthermore, momentum begets momentum. The more that her crowds and selfie-lines become a thing, the more that even less-engaged voters start to think that she must have that 'something' that makes her a good pick for president.

4. The only way to prove you can win, is to win.

Biden has set himself up as the 'most electable' candidate in the race. If he loses in Iowa and New Hampshire, well, the rationale for his candidacy also goes up in smoke. The best way for Warren to prove that she can beat Trump in November is to win in those early states. Obviously, winning a primary or caucus is not the same as proving that you can beat the sitting incumbent president. But, voters like winners. Once a candidate starts to win, it gets harder and harder for the "but can he/she win in November?" to get much traction.

Image: Senator Elizabeth Warren (D-MA) rally at Washington Square Park in New York, New York on September 16, 2019 | Credit: Rainmaker Photo/MediaPunch /IPX

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