LOS ANGELES — The library where Hollywood parents park their children after school and where a line forms most mornings for the public computers is on a list that will go before county voters in November, and its regulars are paying attention.

County supervisors last week placed a library bond on the fall ballot, a borrowing measure its backers say would raise several hundred million dollars to repair, expand and seismically retrofit branches across the county system. If it passes with the two-thirds vote such bonds require, the measure would be repaid over decades through a small annual charge on property owners, the mechanism that makes bonds politically fraught even when the buildings they fund are popular.

For the Hollywood branch, supporters say, the money would go toward work the building has needed for years. A campaign fact sheet lists a seismic retrofit of the older section, an expanded children’s area, and upgraded electrical capacity to support more public computers and charging stations — the amenities that have quietly become the branch’s busiest service.

“On a weekday morning the computers are the library. People come in to apply for jobs, to file for benefits, to do the things you now cannot do without a screen,” said Naomi Farrell, a branch manager, choosing her words carefully because library staff are barred from campaigning for the measure. “I can describe what the building lacks. I am not allowed to tell anyone how to vote on it, and I won’t.”

What the bond would not do is fund day-to-day operations. Bond money by law pays for construction and permanent equipment, not salaries, hours or books, a distinction supporters concede blunts one of the easier pitches. A branch can be retrofitted and expanded and still close early because the operating budget, funded separately, could not staff the new space.

Opponents have seized on exactly that gap. A taxpayer group that opposes the measure argues the county is asking property owners to finance buildings it may struggle to keep open, and that past bonds have left branches renovated but understaffed. “A beautiful empty building at four in the afternoon is not a service,” the group’s spokesman, Curtis Bellweather, said. “Fund the hours first. Then ask us for the walls.”

Supporters counter that the buildings cannot wait, pointing to seismic reports that flag several older branches — the Hollywood section among them — as needing retrofits regardless of the operating debate. They argue the bond addresses the one problem it is legally allowed to address, and that hours are a fight for the annual budget, not the ballot.

The measure needs a two-thirds majority to pass, a threshold that has sunk library bonds before. Ballots go out in October. Farrell said she plans to keep the branch’s sample-ballot display stocked and her own opinion to herself, which she has had, she noted, a great deal of practice doing.