Tuesday’s primary election for the Third District seat on the Santa Barbara County Board of Supervisors offers some unusual twists and turns for a race that could determine the balance of power in county government.

Three candidates from across the political spectrum are running — for the first time since the district boundaries were realigned after the 2020 census.

Traditional politics, party registration, hometown support and money all are likely to play a role in the outcome of an election that is unlike any in recent memory.

If none of the candidates — incumbent Joan Hartmann, and challengers Frank Troise and Jenelle Osborne — receives more than 50% of the vote in the March 5 primary, the top two vote-getters will face off in the Nov. 5 general election.

Hartmann, a Democrat and dependable liberal vote on the board, is seeking a third term, and is far outpacing her opponents in fundraising. She also has powerful backing from the Santa Barbara County Democratic Party.

Challenging her from the right is Troise, a conservative Republican financial expert and investment manager with little name recognition and a limited campaign war chest. He also has been largely unable, thus far, to consolidate strong support from the GOP.

Complicating what otherwise would be a pretty straightforward left-right/Democrat-Republican contest is Osborne, Lompoc’s mayor, who is registered as “no party preference,” and is seen as a moderate.

She trails Hartmann in the money game, but has made gains in that regard in recent weeks.

For decades, the Third District seat on the board has been a battleground between liberals and conservatives, and between the North County and the South Coast.

It has a reputation as being the swing vote on the five-member board, and elections typically have been decided along party lines, even though the seat officially is nonpartisan.

Left-leaning Democratic candidates — usually from the South Coast or the Santa Ynez Valley — have mostly dominated the seat, due to district boundary lines that gave them a clear edge when it came to party registration.

But that changed with the 2020 census and the every-10-years redrawing of the boundaries for the board’s five districts.

Most notably, Isla Vista and its reliably liberal student voting bloc was moved out of the Third District and into the Second District during the redistricting process.

That gave conservatives their first real hope in years to flip the district in 2024 — the first election with the new boundaries.

But several factors have conspired to upend the normal political calculus for the race.

Hartmann is still viewed by most observers as the favorite, with the main question being whether she can eke out a victory in the primary and avoid a fall runoff.

The district’s voter-registration breakdown clearly works in her favor.

Of the 51,275 registered voters in the district as of Feb. 20, 43.2% are Democrats, according to the county Elections Office.

Of the rest, 28.3% are Republicans, and 20.3% have no party preference. The remaining 8.1% are sprinkled among several other minor political parties.

That gives Hartmann a notable edge, especially with the expectation that the local Democratic Party will muster its considerable resources — both money and get-out-the-vote efforts — on her behalf.

Add to that the fact that Troise is a political newcomer and a relative unknown, and GOP hopes to capture the seat have dimmed.

Seasoned political observers have reasoned that Troise lacks two things — money and a high profile — that would be needed to mount an effective challenger campaign against an incumbent.

Moreover, Osborne’s presence in the race could be significant. She is a popular mayor in Lompoc, and is offering a more centrist and homegrown message to voters.

In that context, looking at voter registration provides a tale of many cities.

Goleta, for example, has 53.0% Democratic voters compared to 20.4% Republicans, 20.3% independents and 6.5% other parties.

But not all of Goleta is in the Third District — only roughly two-thirds of the city west of Carlo Drive and San Pedro Creek, a few blocks west of Fairview Avenue, is included in its boundaries.

Lompoc, where Osborne is likely to do well, is 40.9% Democrat, 28.4% Republican and 21.7% independent. And it accounts for almost 39% of all voters in the district.

So it’s possible if not likely that Osborne will eat into Hartmann’s support in the city despite the Democratic advantage. If that is the case, it could deny Hartmann an outright victory in the primary.

The cities of Solvang and Buellton in the Santa Ynez Valley are a different story — much more closely split when it comes to party registration.

Solvang is 37.9% Democrat and 34.8% Republican, with 18.8% independent, while Buellton is 38.3% Democrat, 33.8% Republican and 19.4% independent.

But those two cities only account for 7,329 voters, or 14.3% of the district total, so their impact is limited.

There are other voters in unincorporated areas of the district, but detailed breakdowns for those areas were not available, and their numbers overall are not large — about 9% of the total.

One could easily surmise that the outcome of the election may ride on how the independent vote breaks, and whether Lompoc turns out for its hometown candidate.

The race has spurred lots of discussion and crystal-balling among political wonks trying to read the tea leaves.

One long-time political observer told Noozhawk he thinks “there’s a good chance” Hartmann will win outright in the primary.

In that scenario, the observer said, “Jenelle and Frank split votes and Joan just walks.”

The observer, who is not involved in the race, spoke on condition he not be identified so as to not upset his other clients.

If the race does go to a runoff, the observer believes it will be Hartmann and Osborne.

In support of that view, he pointed to Osborne’s name recognition, popularity in her community, and the fact that Lompoc now makes up a significant portion of the district.

“Janelle is popular, more of a centrist, and more representative of the electorate in the Third District as it’s been redrawn,” he said.

Working against Osborne, he said, is the fact that she was a relatively late entry into the race, which put her behind in fundraising and building a campaign organization.

As for Troise, the observer said he “saw Frank early on as somebody who looked good on paper.”

But he believes Troise is hampered by the lack of unity in the local GOP, which is split between hard-right conservatives and those who are fiscally conservative but socially moderate.

“The party is so out of touch with the electorate in the county,” he noted.

A final factor in the race, the observer said, is turnout, which typically is “abysmal” for primary elections.

Who shows up for each candidate — or doesn’t — could make the difference.

The answer will come next week.