At the beginning of October, Sen. Bernie Sanders (I-Vt.) had a heart attack. On Oct. 15 in the fourth Democratic debate, the moderate Democratic contenders engaged forcefully with Sen. Elizabeth Warren (D-Mass.) on Medicare-for-all. She gave a ringing endorsement of Sanders’s Medicare-for-all and bashed moderates for thinking too small. “Medicare-for-all is the gold standard,” she declared. “It is the way we get health care coverage for every single American, including the family whose child has been diagnosed with cancer, including the person who’s just gotten an MS diagnosis. That’s how we make sure that everyone gets health care.” You would think that the combination of Sanders’s heart attack (sparking concerns about his health from voters) and Warren’s bold defense of Medicare-for-all, now bolstered by a revenue plan, would have powered her well ahead of Sanders. But things have gone far differently.

For one thing, Sanders snagged coveted endorsements from the left, especially the backing of Rep. Alexandria Ocasio-Cortez (D-N.Y.). Moreover, Warren’s surge stalled. Take a date in early October and see where the candidate stood relative to one another. On Oct. 5, for example, in the RealClearPolitics average of national Democratic primary polls, Warren had 25.7 percent to 15.7 for Sanders. As of Nov. 3, Warren was at 20.3 percent and Sanders at 17.1. Huh? Yes, even with a heart attack and Warren’s forceful rollout of her Medicare-for-all plan, she has lost quite a bit of ground against Sanders. In the same time frame, former vice president Joe Biden, pummeled daily by the press and the White House, went from 26.3 to 29.1 percent.

The story is similar at the state level. In Iowa in the same time frame (the last poll being Nov. 1), Warren has been flat (23 percent on Oct. 1 to 22.3 on Nov. 1) while Sanders picked up a few points (13.5 to 15.3 percent) and South Bend, Ind., Mayor Pete Buttigieg soared from 11 to 17 percent. The only one surging in Iowa lately is Buttigieg.

Let’s look at New Hampshire from Oct. 1 to Oct. 29 (the last poll). Warren did go up from 21 to 25 percent, but Sanders went up as well from 17.2 to 20 percent. She might be inching up, but surging? Nope.

There is no doubt that from early in the year to the beginning of the October Warren surged into the top tier. However, as Warren for the first time faced real pushback on her Medicare-for-all stance, while Sanders bounced back from his heart attack with Ocasio-Cortez’s endorsement in hand, the Warren surge stalled and even reversed just a bit.

It will get harder, not easier, for Warren from here on out. For one thing, Sanders is hitting her from the left, accusing her over the weekend of enacting a regressive tax on workers, namely the $9 trillion head tax on employers. “I think that that would probably have a very negative impact on creating those jobs or providing wages, increased wages and benefits for those workers,” Sanders said in an interview with ABC. Meanwhile, the moderates in the race (Biden, Buttigieg, Sen. Amy Klobuchar) have taken the gloves off and now argue that aside from the policy merits, the plan makes Warren unelectable. She is going to take it from both sides in the next debate.

And finally, with battleground state polls showing her doing far worse than Biden or even Sanders in swing states, she will have to once more show she can reach out beyond her base. The problem: She hasn’t even been able to woo Sanders’s base to her side.

It would be a mistake to underestimate Warren. She is more dogged, more disciplined and more organized than any other candidate. However, the media should look at the numbers. Instead of “Can she be stopped?” the question is now “Does she have a glass jaw?”

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