With former Vice President Joe Biden set to enter the 2020 fray on Thursday, the Democratic field contesting the right to challenge President Trump for the White House next year will be a record 20.

Hundreds file each cycle, but only a sliver receive sustained media attention, raise significant amounts of money and are included in televised debates.

For the 2020 Democratic presidential nod, 20 people can be listed as viable contenders, a Washington Examiner analysis found. That included not only fundraising and poll results, but whether television networks have devoted airtime for coverage.

So, spiritual guru Marianne Williamson makes the grade, since CNN recently broadcast an hourlong segment of a town hall-style show with her. Same with entrepreneur Andrew Yang, who has never held elected office. Even former Sen. Mike Gravel of Alaska counts. Gravel was once a serious player in national politics, having gained noteriety — critics say infamy — for reading portions of the Pentagon Papers, about the origins of the Vietnam War, into the public record.

Mirimar, Fla., Mayor Wayne Messam is struggling for media attention and has shaky finances that prevented him from paying campaign staff but is included in most lists of candidates.

In the 1972 race, more than a dozen Democrats ran to take down Republican President Richard Nixon. That honor — or dishonor, considering he lost 49 states — went to Sen. George McGovern of South Dakota.

The next cycle proved much more fruitful for Democrats, as a similarly large bunch vied for the White House. Former Georgia Gov. Jimmy Carter emerged from political obscurity to beat a scrum of better-known rivals and then Republican President Gerald Ford that fall.

And just last election, businessman Donald Trump claimed the Republican nomination, and eventually the presidency, after besting a swath of more established politicians. That field included former Florida Gov. Jeb Bush, Sen. Marco Rubio of Florida, Sen. Ted Cruz of Texas, and many others with decades of experience in public service.

The 2020 Democratic field is even larger. Historians and political commentators have described the state of the race as "unique," "exceedingly rare," and "unprecedented" given past events. The stage is already set for a battle over not just the party's nomination, but for resources and support to buoy their campaigns.

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In addition to Biden, the front-runner according to a slew of early polls, there's Gabbard and Buttigieg, the latter of whom has steadily risen in opinion surveys as he's conducted scores of media interviews. Six senators are running for the Democratic nomination: Cory Booker of New Jersey, Kirsten Gillibrand of New York, Kamala Harris of California, Amy Klobuchar of Minnesota, Bernie Sanders of Vermont, and Elizabeth Warren of Massachusetts.

Several House members are also running, though nobody has gone directly from that chamber of Congress to the Oval Office since James Garfield's election in 1880. Still, Reps. Seth Moulton of Massachusetts, Tim Ryan of Ohio, and Eric Swalwell of California are running, along with ex-congressmen John Delaney of Maryland and Beto O'Rourke of Texas. Former Obama administration housing secretary Julián Castro, ex-Colorado Gov. John Hickenlooper, and Washington Gov. Jay Inslee round out the list.

O'Rourke, 46, who earned a national reputation in 2018 during a close loss to Cruz running for Senate, is touting the field as a positive for the Democratic Party's chances of ousting Trump from office in November next year.

"Overall, this is a really good sign for those who want to beat Donald Trump in 2020," O'Rourke said in an email to his database. "More competition, more ideas, and more energy will help us win the White House."

Then O'Rourke turned to his real reason for writing: "But with so many candidates running, we run the risk of falling behind if we don’t raise enough money to compete hard in these early stages. That’s why we’re asking now."

According to James Thurber, the director of American University's Center for Congressional and Presidential Studies, the campaigns will deploy "a whole different strategy and tactics in this kind of multi-candidate war," adding it remained to be seen whether they would resist going negative, attacking personalities and family members, or distorting policy positions.

"Look to also the Republican Party and what happened last time. Sometimes not the strongest candidate jumps out of the pack with not a lot of support from the party," Thurber told the Washington Examiner of Trump's 2016 victory.

Thurber said, however, it was still too soon to generalize about whether large fields in the past two cycles meant a new norm in presidential politics.

Boston University history professor Bruce Schulman explained how the Democratic system dates back to 1972 after 1968 Democratic presidential nominee Hubert Humphrey, the former vice president, became the party's standard-bearer without competing in any of the primary caucuses or elections.

"As late as 1968, party leaders controlled the nominating process and the conventions decided the nominees," Schulman told the Washington Examiner.

But Schulman suggested the breadth of the historic field could bode well for Democrats.

"The Democrats had a large field in 1972, 1976, 1988, and 1992. The GOP in 1968, 1980, 1996, and 2016. The eventual Republican nominee won three out of the four times there was a big field. The eventual Democratic won two out of four times. If you add that up, it's five out of eight," he said. "Since World War II, when an incumbent president ran, he won eight out of the 11 races. So it’s hard to beat an incumbent president. But all three times the incumbent was beaten, there were a lot of primary contenders in the opposition field. Of course, two of those three times were in recessions too."

Reviewing past crowded Democratic fields look like a who's who of big-name politicians from their eras beside other forgotten figures in today's political environment.

McGovern in 1972 overcame challenges for the Democratic nomination from Humphrey, Sens. Birch Bayh of Indiana, Fred Harris of Oklahoma, Vance Hartke of Indiana, Henry Jackson of Washington, and Edmund Muskie of Maine, along with former Sen. Eugene McCarthy of Minnesota, whose 1968 candidacy helped topple former President Lyndon Johnson over Vietnam.

Former North Carolina Gov. Terry Sanford also ran, as did previous Alabama Gov. George Wallace, whose 1968 racially-tinged presidential campaign as the American Independent Party nominee proved one of the best third-party efforts in American history.

Further down the 1972 Democratic presidential roster are names more likely to be remembered by political junkies, including Reps. Shirley Chisholm of New York, Wilbur Mills of Arkansas, and Patsy Mink of Hawaii; Del. Walter Fauntroy of Washington, D.C.; and former mayors John Lindsay of New York City and Sam Yorty of Los Angeles.

Four years later, Carter came from seemingly nowhere to vanquish a similarly high-profile group of rivals, including Bayh, Sanford, and Wallace. Additionally seeking the nomination that year, in the shadow of Watergate, were California Gov. Jerry Brown, Sen. Frank Church of Idaho, and Rep. Mo Udall of Arizona.