Democratic dare

With today's announcement by former Arkansas governor Mike Huckabee that he will seek his party's nomination for president, the Republican candidate field has doubled within the last 48 hours. Just one day earlier Carly Fiorina and Ben Carson had entered the race.

And there is no end in sight for conservative hopefuls vying to succeed Barack Obama. Jeb Bush, arguably the favorite to head the Republican ticket, has not even formally declared his bid. Ultimately, the Republican roster could expand to 20 candidates.

Things couldn't be different on the Democratic side. If it hadn't been for Vermont Senator Bernie Sanders deciding to join the race last week, Hillary Clinton, would have remained the sole Democratic presidential candidate for 2016. And the prospects for the Democratic race widening are slim.

Holdout Martin O'Malley

The only expected, yet still undeclared, contender to enter the race is former Maryland governor and Baltimore mayor, Martin O'Malley, who is currently receiving unwanted attention for his political legacy in Baltimore. With the two biggest Democratic names, Vice President Joe Biden and Massachusetts Senator Elizabeth Warren, not inclined to run, that leaves Jim Webb, a former Virginia Senator, as one of the few other possible Democratic candidates.

So why is it that so far only two and probably no more than four Democrats want to run for President in 2016?

There are two reasons. The first one is called Barack Obama. The second goes by the name of Hillary Rodham Clinton.

"It's very hard to win three presidential elections in a row, so all else being equal and even if Hillary Clinton didn't exist, it isn't a great cycle to run if you are a Democrat," said Thomas Schaller, chair of the political science department at the University of Maryland, Baltimore County.

Scared by Hillary

In fact, it is almost impossible to keep the White House after your party controlled it already for eight years. The only time this happened since World War II was in 1988 when Republican Vice President George Bush senior won after eight years of Ronald Reagan. The last time the Democrats held the presidency for 12 years in a row was in 1940 when Franklin Roosevelt under extraordinary circumstances won a third term.

As for the second reason, when former Secretary of State Hillary Clinton decided to run that simply took the air out of most remaining contenders who may have been mulling a run after eight years of a Democratic presidency.

"Most Democrats have just been scared off entering," said Julian Zelizer, professor of history and public affairs at Princeton University. "They realize that when you have someone of this stature and caliber that a lot of the fundraising will be difficult, that a lot of the voter attraction process will be difficult. And I think part of it is simply being intimidated by Hillary Clinton."

Despite Clinton's recent troubles involving emails sent from a private account during her stint as Obama's top diplomat and questionable foreign donations to her husband's foundation during the same period, most indicators - polling, name recognition, money - show that the Democratic race could indeed be a foregone conclusion.

Clinton's deja vu

"Unless one of these scandals or issues with the Clinton Foundation becomes a bigger problem than they are, I don't think there is much chance that anyone is going to defeat her," said Zelizer.

Ironically, the same public sentiment - that Clinton was invincible - was prevalent eight years ago - until a largely unknown candidate named Barack Obama shattered it. Such a miracle contender, however, is nowhere to be seen this time around. And that her two opponents, Bernie Sanders and Martin O'Malley, can really mount a credible and sustained challenge against Clinton seems currently hard to fathom.

"If she creates opportunities I suppose it's possible, but it's pretty unlikely," said Schaller. "I don't think she is going to make the errors she made eight years ago, but you never know."

That's why, barring any major glitches or new scandals, the Democratic primary season 2016 could end before it really gets started with the Iowa caucus on February 1.

"If there are no surprises this could be over very early within a month or two of the primaries and caucuses which would be good for her in that she could quickly turn her attention to the GOP," said Zelizer.