Joe Biden who? Sen. Elizabeth Warren (D-MA), who for weeks has been steadily gaining on the former vice president in the 2020 Democratic primary, has officially overtaken him in the RealClearPolitics average, one of the best gauges for 2020 polling. Warren has bested Biden by .02 percent. She's at 26.6 percent, while Biden is at 26.4 percent.

And there it is: Warren takes lead over Biden in RCP National Average. https://t.co/YJZbUNCfzm — Tom Bevan (@TomBevanRCP) October 9, 2019

Sen. Warren's progressive message can explain the momentum. But, Democratic voters have also started to question whether Biden can cross the finish line. At 76 years old, his age is starting to show. His primary opponent Julian Castro exposed Biden's faulty memory at the last debate, while President Trump has told the press that Biden "isn't playing with a full deck."

It's not just his age, though. He has that whole Ukraine scandal to deal with. His son, Hunter, sat on the board of a corrupt Ukrainian gas company and reportedly received hundreds of thousands of dollars for the gig. Biden reportedly tried to get the prosecutor investigating the company fired. Instead of addressing the controversy head on, Biden has been lashing out at reporters who are simply doing their jobs and asking the questions.

Then we have pieces like this from The New Republic, suggesting Biden's campaign is leaning on an antique campaign platform.

But while Obama seemed to herald the possibility of a new political future, Biden has promised a return to our political past, or at least the version of that past he remembers. The American past was, at most, a nebulous source of inspiration for Obama. Biden is of it. What Obama insisted—and still insists—is on our collective horizon, Biden sees in his rear-view mirror. It is the same destination; for one just ahead, the other just behind.

Sen. Bernie Sanders (I-VT) came in a distant third in the RCP poll with an average of 14.6 percent, followed by an even more distant fourth placer South Bend, IN Mayor Pete Buttigieg with 5.6 percent, and Sen. Kamala Harris (D-CA) at fifth place with 4.4 percent.