Former Supervisor and (briefly) Mayor Mark Farrell leads incumbent Mayor London Breed by the slimmest of margins in a new poll, with Daniel Lurie and Supervisors Aaron Peskin and Asha Safai trailing. But over a quarter of voters polled said they were still undecided about the race.

This is the first time in many years that San Francisco will have a mayoral election in the same cycle as a national general election, which will hopefully mean more voter turnout and a more competitive race all around. And San Francisco's ranked-choice voting system is sure to keep us from a definitive answer about who our next mayor will be for at least a week after the election occurs, if not more.

KRON4 just conducted their own poll, in conjunction with Emerson College, which found that Mark Farrell would take 20.6% of first-choice votes if the election were held today, and Breed would take 20.3% — a statistically insignificant difference given a margin of error of 3.5%.

Daniel Lurie trails behind with 17.5% of first-choice votes, but he could be a dark-horse contender via ranked choice — he takes 21% of the second-choice votes in this poll, which is well above Breed's 12.8% and Farrell's 14.7%. That could easily catapult him into leading position as the ranked-choice rounds shake out, especially if those who are undecided start to favor him.

The KRON4-Emerson College poll found that 26.5% of potential voters still have no first-choice candidate, and even more, 26.8%, had no second choice yet.

"It is the undecided vote that is ahead in this poll,” says Sonoma State University Political Science Professor David McCuan, speaking to KRON4. "But as voters begin to turn their attention, some interesting things happen as we start to look at second and third choices."

Still, things don't look great, with seven weeks until the election, for Peskin and Safai. Peskin had just 8.5% of first-choice votes, and he comes in lower for second- and third-choice votes in this poll. Safai has a dismal 1.6% of first-choice votes in the poll, likely marking his lack of name recognition outside his district.

With 13 total candidates in the running for mayor, it will take a couple of rounds ranked-choice tallying before we see Peskin and Safai drop off. But if these numbers hold, this will likely be a three-way contest and those third-choice picks could matter a lot — especially if a large progressive bloc of voters has Breed as their second or third choice.

KRON4 notes that this is the first poll to be conducted since the high-profile September 1 shooting in Union Square that injured 49er rookie Ricky Pearsall — something that Farrell, however tackily, quickly looked to spin to his advantage.

And the shooting may, in fact, have damaged Breed's candidacy, at least for the week this poll was conducted. An early August poll conducted by the Chronicle had Breed with a eight-point lead over Farrell — 28% to 20% — in first-choice votes. If the KRON4 poll is accurate, that's a pretty steep loss of support in a matter of a month.

Things could still change. Breed's approval numbers haven't exactly been great in the last year and a half, yet she's remained a strong contender in this race, and looked to be in a strong position just a few weeks ago. You may recall that back in January, as this race was still taking shape, a poll commissioned by Lurie's campaign had him in the lead by 18 percentage points — but yes, that was a poll his campaign commissioned.

What we do know is that a shit-ton of money is being spent on this mayoral race, including a lot of Lurie's and Farrell's own personal wealth.

And the mud-slinging has only just begun.

Previously: More Fake SF Mayoral Candidate Websites Flooding the Zone Before Election Day

Top image: (left) Photo by Justin Sullivan/Getty Images; (right) Photo by Arun Nevader/Getty Images