Most Democratic candidates bolting from impeachment to Iowa to get in a shortened weekend of campaigning one week before the Iowa caucuses.

And this morning we have a brand new ABC News Washington Post poll suggesting Joe Biden remains ahead, Bernie Sanders rising and Elizabeth Warren dropping significantly from our last poll in November Among registered voters.

A veces Rachel Scott is in Des Moines with more.

Good morning to you, Rachel.

Even good morning.

That's right, former vice president Joe Biden and Senator Bernie Sanders emerging to the top of the pack.

But when it comes to the issue of electability, who voters think has the best chance of beating President Trump, Biden leads by a wide margin.

This'll morning, Joe Biden OutFront bolstered by voters who believe he has the best shot of defeating President Trump.

My look at Donald Trump.

What he stands for, how he behaves, what he's done.

My response is always the same.

We are so much better than Donald Trump, so much better.

Thief.

Former VP Holding a steady lead in our latest ABC News Washington Post Poll, Senator Bernie Sanders, on the rise trailing close by Senator Sanders.

Are you excited about getting to Iowa?

Vermont senator sprinting from the impeachment trial back out to the campaign trail?

Sanders is boning moments, particularly here in Iowa, eight days out from the first vote, making his own electability argument.

If we are successful in getting young people in big ways involved in the political process, getting working, people have given up on the political process.

The vote we will not only defeat Trump, we will defeat Trump badly the rest of the pack further behind Senator Elizabeth Warren, dropping 10 points in our poll but picking up an endorsement from the Des Moines Register, dancing with excitement as she learned the news.

I just heard, and I'm delighted, Um, it really means a lot.

But the four senators and the race will be pulled back to Washington tomorrow for the impeachment trial.

I would be here every day if I cut their rivals capitalizing on their absence during the final stretch ahead of the Iowa caucuses.

We have to find a lot of expectations, part of success, and this race is fluid.

There is still room for movement.

53% of Democratic leaning voters polled say they would consider supporting a different candidate.

Dan Rachel Scott right there in Iowa.

Thank you, Rachel.

So much to talk about.

So let's bring in our ringer.

ABC News chief anchor George Stephanopoulos.

He's gonna be hosting this week later this morning a ringer before.

Well, get used to it.

George.

Great to see you.

So let's start with Bernie Sanders.

Hey, seems to be, uh, the receiving end of a lot of momentum, both nationally and in Iowa.

What do you what's going on?

Especially in Iowa, and I think it's a few things and number when he said that the clearest message clears most consistent message.

He's got experience as a candidate.

Remember, he ran last time around, and that gave him a fundraising juggernaut as well.

He's got the hardest core of committed supporters.

One of things our poll shows you're seeing.

The same things in the Iowa polls is that a lot of his game has come at the expense of Elizabeth Warren.

He's held on to the true believers as she's equivocated a bit on this Medicare for all plans.

So I think that's what's behind his rise right now.

Let's talk about Joe Biden in our poll.

He seems to be hanging tough nationally at the very least.

But he could be in for a choppy week here because the Republican, the Republicans, that the defenders of President Trump in the Senate trial are gonna be talking about the Bidens a lot during the impeachment trial.

Could that hurt him?

As we run upto Iowa, I'm not sure it hurts him.

If you actually look at the polls going back to late September October, when this story first broken impeachment proceedings actually began, Joe Biden's actually held study even improved his standing among national polls.

Listen, if your Democratic primary voter and the president's attacking us, his chief opponent, that gives a lot of them reason to think.

Wait.

The president's scared of Joe Biden.

That could mean he's the most electable.

That may end up helping him a CZ, much as it hurts him.

Speaking of the Senate trial, we've seen this new.

Now we have video of this interaction, apparently between the President and left Parness, where the president is saying, Hey, fire the ambassador to the Ukraine allegedly, Do you think this has any impact on the trial going forward?

doesn't appear to be, I mean, one of things that shows his delivery pointed out in his piece that the president of Citizen No left Corner there's a lot of evidence to the contrary right there.

The Democrats are hoping that new evidence like this that has been coming out just about every day would fuel their argument for no witnesses and documents in the Senate.

And even though that issue is enclosed yet and you still have senators like Mitt Romney, Susan Collins of Maine suggesting they're open to new witnesses, the positions do seem to be hardening over the course of the week.

And I think that even Chuck Schumer, the Democratic leader in the Senate, said yesterday that the fight to get new witnesses is very, very tough.

George Stephanopoulos, thank you very much.

Great to see you are ringing on a Sunday morning.

And don't forget, George has a big show this morning.

He has two big exclusive interviews House impeachment manager Congresswoman Val Demings and a juror in the ongoing trial, Republican Senator James Lankford.

That's all coming up on this week later this morning right here on ABC and speaking of George, he tomorrow morning will be leading our live coverage of the Senate impeachment trial when it resumes starting at 10 Eastern right here.

That's correct.

One afternoon, Eastern, as I said one right here on ABC.

And by the way, since we're promoting stuff here, we want to tell you that we're counting down to the launch of ABC News.

Live breaking news, context and analysis, digging deeper and making sense of it all.

It launches on Monday night.

February 3rd.

Hi, everyone.

George Stephanopoulos here.

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