Even as Democrats brace themselves for the inauguration of Donald Trump as the nation's 45th president, they are focused on 2020 and on who can help them recapture the White House.

No Democrat has yet declared any interest in running for president, but the successful candidate for 2020 will have to be somebody who has a record of accomplishment, played a key leadership role in opposing Trump's policy initiatives, can win Democratic primaries that will be dominated by liberals, turn out black, Latino, young, and low-income voters, and win back some white, working-class, swing-state voters who voted for Trump.

One has to assume that the next Democratic candidate will by facing off with Trump, but it is possible that he won't want to run again or that he will be dethroned by the Republicans after causing enormous chaos and intra-party division. In that case, the most likely GOP candidate will be House Speaker Paul Ryan. Vice President Mike Pence will want to run, too, but he'll be saddled with the Trump legacy and, in any case, won't have Trump's wider appeal.

For the past half century, the path to the White House has been easier for governors than for senators. The current pool of Democratic governors, particularly those from swing states who could appeal to independent voters, is particularly shallow.

A strong Democratic candidate will need to draw a sharp contrast with Trump, Ryan, or Pence, all extreme conservatives. She or he can't be too close to Wall Street, and must have a credible plan to promote jobs, improve the safety net for families, expand health care while controlling drug and insurance costs, expand workers' rights, protect reproductive health, limit military-style assault weapons, challenge racism in the criminal-justice system, and strengthen consumer and environmental protections. To win, the Democratic nominee will also need to be someone with charisma, able to withstand the Republican attack machine, and be free from personal controversy.

It's a tall order-and none of the close to two dozen Democrats who might be considered contenders passes every single one of these litmus tests. Nevertheless, here is a handy user's guide that shows how 20 potential Democratic presidential hopefuls stack up. They are ranked here according to two criteria-whether they are progressive and electable-on a scale of 1 to 5, with 5 being the highest.

In the "progressive" column, the ranking takes into account the individual's track record in office (including voting records where applicable), and comments on issues, especially on economic and social topics. Only a few of them have much experience with foreign policy. The "electable" column ranks potential candidates on their own electoral track records, their potential appeal to both swing voters in battleground states and Democratic base voters, and their ability to deliver 270 Electoral College votes.

Two Democrats on this list-Kamala Harris and Tammy Duckworth-are newly elected senators who will only have served four years by 2020, but that didn't hurt Barack Obama in 2008. Several others are wild cards, such as businessmen Mark Cuban and Howard Schultz. Like Trump, who also had no electoral experience, both have potential popular appeal.

Here is a Progressive/Electable ranking for 20 Democrats whose names have been mentioned as potential White House candidates:

Progressive | Electable

Senator Elizabeth Warren of Massachusetts: 5 4.5

The charismatic Massachusetts

senator leads the party's progressive

wing as a foe of Wall Street.

Senator Sherrod Brown of Ohio: 5 4

If Ohio's Brown wins re-election in

2018, he could help the Democrats win

back the Rust Belt in 2020, particularly

with his longstanding record in support

of fair (not "free") trade.

Senator Bernie Sanders of Vermont: 5 3.5

Many of his supporters and some pundits

thought Sanders could have beaten

Trump, but others question his

commitment to the Democratic Party,

and he'll be 79 in 2020.

Secretary of Labor Tom Perez: 4.5 2.5

The most progressive member of Obama's

cabinet has lots of government experience

and a broad following within the party, but

hasn't yet been tested in a major election.

California Lieutenant Governor Gavin Newsom: 4.5 2

The former San Francisco mayor-who led

the fight for same-sex marriage and

municipal health insurance-is now the

frontrunner to succeed Jerry Brown as

governor in 2018.

Senator Kamala Harris of California: 4 2.5

The Senate's only African American woman

was a popular consumer advocate as

California's attorney general.

Senator Kirsten Gillibrand of New York: 3.5 4

Many Democrats view her as a young

version of Hillary Clinton, but without

the baggage and the decades-long

resume.

Former Maryland Governor Martin O'Malley: 3.5 3

The one-time Baltimore mayor was

overshadowed in the 2016 Democratic

presidential primaries by Clinton and

Sanders.

Senator Tim Kaine of Virginia: 3.5 2.5

The former Richmond mayor and

Virginia governor has wide-ranging

experience and a down-to-earth

personality, but disappointed a lot of his

fans as Hillary Clinton's running mate.

Senator Tammy Duckworth of Illinois: 3 3.5

This newly elected senator is a disabled

Iraq War veteran who was a popular

congresswoman with a compelling

personal story.

Senator Amy Klobuchar of Minnesota: 3 3

With Midwestern roots, an Ivy League

pedigree, and "Minnesota nice,"

Klobuchar has twice won Senate

elections in what might be turning

into a key Midwestern swing state.

Senator Cory Booker of New Jersey: 3 3

The charismatic black senator and

former Newark mayor has a great

personal story, but some progressives

consider him too close to Wall Street,

and too cozy with wealthy charter

school advocates.

Montana Governor Steve Bolluck: 3 3

While Trump won red state Montana with

56 percent, Bullock was elected to his

second term as governor, raising the

prospect that the prairie populist (he

expanded Medicaid and is pro-union,

pro-gay marriage, and pro-choice) could

help Democrats win back some key Western states.

Colorado Governor John Hickenlooper: 3 3

He's popular in this important swing state,

but environmentalists say he's too close to

the fracking industry.

Former Massachusetts Governor Deval Patrick: 3 2.5

A former civil rights lawyer and two-term

governor who was raised by a single

mother in Chicago, Patrick went on to

Harvard College and Harvard Law School,

but since leaving office he's become a

corporate lawyer-not the best credential

for winning over progressive Democrats.

New York Governor Andrew Cuomo: 3 2.5

New York's progressives have a love-hate

relationship with the unpredictable and

often abrasive Cuomo, who has recently

been moving left to catch up with the

Democratic base.

Senator Chuck Schumer of New York: 3 2.5

Wall Street's favorite Democrat, now the

Senate minority leader, is a progressive

on social issues but would be a hard

sell outside blue states.

Starbucks CEO Howard Schultz: 2.5 3

A moderate Democrat with liberal social

views, Schultz was raised in public housing,

played sports in college, and wound up

piloting Starbucks' dramatic expansion as

its CEO.

Entrepreneur/investor Mark Cuban: 2.5 3

The billionaire businessman owns the

NBA's Dallas Mavericks, chronicled

his success in How to Win at the Sport

of Business, likes to pontificate about

politics on TV talk shows, and once

claimed that if he ran for president

he "could beat both Trump and Clinton."

Outgoing HUD Secretary Julian Castro: 2.5 2

The Latino cabinet member was briefly in

the national spotlight when Clinton

considered him as a possible running mate,

but he was viewed as too young and too

conservative to make a big enough dent

in the electorate.