The Countdown: All eyes on Sanders, Biden, Warren and their ability to challenge Trump for 4th Democratic debate

NEW YORK (WABC) -- Just in time for the fourth Democratic presidential debate, a race that had been largely static through the summer has tumbled into a chaotic fall, shaped by unpredictable events and the deepening impeachment crisis surrounding President Donald Trump.

Less than four months before voting begins, front-running candidates are facing urgent questions about their ability to challenge Trump, prompted by a health scare for Sen. Bernie Sanders, an uneven response by Joe Biden to the president's efforts to tie him to the impeachment inquiry and questions about liberal Sen. Elizabeth Warren's electability.

Political experts join Bill Ritter for "The Countdown" to discuss their predictions for Tuesday night's debate including: Political consultant Hank Sheinkopf, ABC News Deputy Political Director MaryAlice Parks, Cheyenne Haslett with Warren's campaign, Molly Nagle with Biden's campaign and Adam Kelsey with Sanders' campaign.

"This is really about Bernie Sanders being distracted - it's also about Joe Biden trying to figure out whether he belongs because he's been knocked around an awful lot and ultimately it's about whether Elizabeth Warren can ever - and it's not likely - be pushed off track. And if she's not, this Warren express will just continue," Sheinkopf said.

Aside from all eyes on Sanders after his health scare and Biden after recent attacks by the president, the experts agree Trump will be front and center throughout this debate in a way he has not been before.

"Right now we've seen the impeachment inquiry really rev up both bases and that's kind of to be expected, the president believes it's going to rev up his base, democrats think this is showing their most loyal supporters that they have their back, the country's back, the question as is often the case, is what happens with independents and so far democrats really like the polling numbers. We have seen independents in pretty large numbers start to back the impeachment inquiry," Parks said.

The experts predict independents will ultimately determine the outcome of this election.

(The Associated Press contributed to this report).

----------
*Follow us on YouTube
* More local news
* Send us a news tip
* Download the abc7NY app for breaking news alerts
Copyright © 2019 WABC-TV. All Rights Reserved.