CNN  — 

With less than two months before the first votes of the 2020 presidential race, Joe Biden has re-emerged as the clear front-runner for the Democratic nomination.

That simple statement, which is borne out in national and early state polling, seemed unimaginable as recently as two months ago as the former vice president looked to be badly losing altitude on virtually every measure of viability – from debate performances to fundraising to polling.

So, how did Biden turn it around? That answer isn’t simple – it never is! – because it was no single factor. But among the reasons for Biden’s resurgence are a) the struggles of Sen. Elizabeth Warren (D-Massachusetts) b) skepticism over the “Medicare for All” health care plan backed by Warren and Vermont Sen. Bernie Sanders and c) President Donald Trump’s relentless focus on Biden and his son, Hunter.

Before we get anymore into why it happened, let’s look at the unquestioned steadying of Biden’s standing in the race.

In the Real Clear Politics national polling average, Biden has now opened up a double-digit lead over his nearest competitor – Sanders. That’s a remarkable change since early October when Warren had actually overtaken Biden in the RCP national average.

And while Biden has never been as strong a favorite in the early states as he has been nationally, his numbers in Iowa and New Hampshire are looking better of late, too. In RCP’s Iowa average, Biden is in the lead pack. The most recent New Hampshire poll puts Buttigieg at 18% to 17% for Biden and 15% for Sanders. In Nevada, Biden has a 9-point edge over Warren in the RCP averages. And in South Carolina, Biden remains a strong favorite – up 20-ish points in nearly every survey taken in the Palmetto State.

Even beyond the first four states that will vote in February, Biden’s numbers are looking healthy. In new CNN polling looking at the Texas and California primaries – both set for Super Tuesday on March 3 – Biden stands in prime position. In Texas, Biden holds a wide 20-point lead over Sanders. In California, Biden is at 21% to 20% for Sanders and 17% for Warren.

While none of those poll numbers make Biden a lock to win any state – with the possible exception of South Carolina – it shows that he is ahead or very close to the lead in virtually every state set to vote over the first six weeks of the nomination contest.

And then there is the fundraising chase. Biden, a notoriously unwilling fundraiser, showed less than $9 million in the bank at the end of September – a total that left him lightyears away from where Sanders, Buttigieg and Warren were at that time. But since October 1, things have turned around for Biden. In a memo sent to reporters, Biden’s campaign manager said that as of December 1, he had already raised, in two months, more than the $15.6 million he brought in over the previous three months. The Biden campaign credited the increasing money flow to a surge in online donations tied to Trump’s repeated attacks on Biden and his son, Hunter, over their actions in Ukraine. (Side note: There is no evidence suggesting either Biden did anything wrong in Ukraine.)

It’s impossible to see what has happened to Biden’s numbers without acknowledging Trump’s role in it. Contrary to the advice of his advisers, the president has repeatedly attacked Biden – on and offline. Which has had the effect of making Biden’s argument for him – that he is the strongest Democratic candidate against Trump and that the incumbent is afraid of him.

“He’s afraid of just how badly I would beat him next November,” Biden said of Trump while campaigning in Nevada In October. In the November presidential debate, Biden made much the same argument: “I’ve learned something from these impeachment trials – I’ve learned that Donald Trump doesn’t want me to be the nominee. Vladimir Putin doesn’t want me to be president.”

The more Trump attacks Biden, the more a sense of Biden-as-de-facto-nominee sets in.

What else is going on here? Well, it appears from a close examination of the polling that more pragmatic voters with an eye on nominating someone who can avoid being caricatured as a socialist or a wild-eyed liberal are beginning to assert themselves. Hence Warren’s slight fade and the increase in support for Biden, Buttigieg and, especially in Iowa, Minnesota Sen. Amy Klobuchar. Polling also suggests that voters are skeptical – at best – of getting rid of all private health insurance as would happen under “Medicare for All.”

All of this could be, of course, be temporary. Polls – and momentum they reflect – can change and change rapidly when people are paying close attention and actual votes near.

But at this moment, Biden is riding as high as he has since the early days of his candidacy. Which is a big deal.