Former Secretary of State Hillary Clinton continues to lead the 2016 Democratic presidential field — it's not even close — but another Clinton administration is far from a sure thing, even if the election were held today: A new poll out Wednesday shows that even as the clear Democratic favorite, she would face stiff competition from several would-be GOP candidates.

The new Quinnipiac survey has Clinton with support from a whopping 57 percent of Democrats, followed at a distant second by Massachusetts Sen. Elizabeth Warren, at 13 percent. Vice President Joe Biden trails with 9 percent, while no other candidate breaks the 4 percent threshold.

Clinton has yet to announce whether she will run but is widely expected to enter the race. The vice president has publicly flirted with the idea of running, while Warren has so far dismissed the possibility of a 2016 candidacy.

The field is far less clear on the GOP side, where former presidential candidate Mitt Romney remains the favorite with 19 percent support. The 2012 Republican presidential nominee has publicly said that he is not interested in mounting a third presidential bid. The poll has former Florida Gov. Jeb Bush following Romney among GOP voters with 11 percent support.

When Romney is taken out of the equation, Bush leads with 14 percent support, is followed by New Jersey Gov. Chris Christie at 11 percent. Both Bush and Christie have said publicly that they are considering throwing their hats in the ring, but have not formally entered the race.

Despite Clinton's enormous lead among potential rivals in the Democratic primary, the survey indicates she would struggle against several GOP candidates. Romney has 45 percent to Clinton's 44 percent, if the election were held today. And Clinton would have 43 percent to Christie's 42 percent.

She is a clearer favorite when matched against other GOP candidates, with a 46 percent to 41 percent edge over Bush, and a 46 percent to 42 percent advantage over Wisconsin Rep. Paul Ryan. And Clinton trounces Texas Sen. Ted Cruz, 48 percent to 37 percent.

The telephone survey of 1,623 registered voters was conducted by cell phone and landline between Nov. 18 and Nov. 23. The survey has a margin of error of plus or minus 4 percentage points.