Another contender has emerged to challenge Joe Biden’s seeming untouchability.

After a series of gaffes again raised question of Biden’s mental acuity, the quiet rise of Elizabeth Warren became significantly louder. She is currently 9/4 (+225) to win the Democratic nomination, just ahead of Biden, who is 5/2 (+250). Bernie Sanders is third at 6/1 (+600).

In Presidential odds, Warren was onec in the mid-teens but is now 5/1 (+500), outpacing every other Democrat and second only to Trump among all contenders. Biden is at 13/2 (+650).

While the question remains whether this is just another blip on Biden’s way to the nomination, it’s important to consider her surge on its own merits.

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Warren’s Early-State Strength

In addition to Biden’s struggles, there’s reason for optimism for Warren on her own terms. The most recent Iowa polling, while outdated, shows her in a strong second place with 19 percent of the vote. Biden still has a nearly 10-point lead over her, but no other candidate breaks double digits other than Kamala Harris at 11 percent, and she’s due for a fall if her national polling is an indication.

This is crucial because the Iowa Democratic caucuses require 15 percent from a candidate. Those who fail to reach that threshold at any caucus location have their candidates redistributed to “second choices.” The field is set to significantly narrow after Iowa, and there’s lots of room for Warren to make a significant pickup.

Warren has also shown strength in California. The most recent polling shows her passing Harris for second place, with 21 percent to Biden’s 25. As the most populous state in the country and decidedly Democratic, California carries a huge number of Democratic delegates, meaning she could keep pace with Biden well into the race.

The Road Ahead

Like the short heyday of Harris before her, Warren’s reign atop the Democratic odds eventually will have to contend with the fact that Biden is still unchallenged in the polls, while the attention hasn’t yet translated into action at the polls.

A new CNN poll shows her struggling to keep pace with Sanders for second place, with barely half Biden’s vote share. And if that doesn’t change, it may only serve to strengthen Biden, as each wave of challengers has a brief moment in the sun (caused largely by priced-in issues) but none can mount a sustained challenge.