Now is a critical time for the Democratic primary. After the September debate, the candidate field is coming to a crossroads. Ostensible front runner vice president Joe Biden is slipping in the polls and the hearts of voters. Biden's moderate platform that criticizes the cost of reforms might be appealing to some, but his old age, countless remembrance gaffes, and traditional views on racial and cultural issues are already turning many liberals away. Combined with a bad track record in presidential elections, Biden will likely fail to win any of the initial state primaries. So here are my top five candidates besides Biden who should be considered legitimate contenders.

Senator Bernie Sanders (I-VT) started his campaign strong with a record number of individual donations. Even though his throat became hoarse from intense speaking on the campaign trail, he retains his fiery passion to fight inequality and injustice. But Bernie keeps repeating much of the same during debates, and he refuses to directly attack the top competitors. Bernie will remain a strong choice, but until he convinces moderates to support his leftward platform, he will falter.

Senator Elizabeth Warren (D-MA) keeps steadily rising in the polls, thanks to a continuous release of new proposals and her sympathetic personality. Her biggest disadvantage is Bernie's existence, which crowds out her progressive support. But she comes across and more caring and relatable on many economic issues. Her rhetoric is less fierce than Bernie's, but she basically matches his leftward bona fides. She keeps doing well in debates and will go far in the primary season.

Philanthropist Andrew Yang is a tough person to analyze after the raffle stunt. On the one hand, he supports progressive ideas like universal healthcare and peaceful foreign policy. On the other, he likes school vouchers and a libertarian version of universal basic income. Drawing support from the right and the left can seriously hurt him in the Democratic primary. How he responds when attacked by a fellow candidate will be key. Yang remains the dark horse with an unlikely path.

Senator Kamala Harris (D-CA) has lost luster since the first debate when she slammed Biden. She straddles a tricky position between centrist and progressive and includes a controversial past as California's top cop. Though she has quality proposals in her middle class tax cut and universal healthcare plan, she prefers to spend time attacking Donald Trump instead of arguing policy merits. She is a top choice for voters who hate Trump and want a prosecutor to dethrone him.

Former Representative Beto O' Rourke is only a top contender due to his bold debate night gambit. While he was known for losing a close battleground election, a command of Spanish, and more libertarian views on trade and immigration, now he is the best choice for gun control advocates. The risky call to confiscate assault weapons nationwide makes him a popular but contentious figure. If the country's gun reform zeal is not enough, he will fall back to a minor underdog.

The rest of the candidates performed poorly or have sustained low poll numbers. They will likely fail to qualify for the next debate after October. It is unclear how the DNC will divide the next debate with the addition of billionaire Tom Steyer and perhaps Marianne Williamson and Tulsi Gabbard. Finally, candidates will be more pressured to prove how they will confront and defeat Trump. The balance between electability and policy is crucial.

The author is an independent voter sharing his own opinion.