Construction unions awarded work on the Mario M. Cuomo/Tappan Zee Bridge have donated nearly $800,000 to Gov. Andrew Cuomo’s campaigns since 2010, according to a new report.

About a dozen unions have worked on the $3.9 billion project, which included dismantling the old Tappan Zee and building the new one named after the governor’s late father, according to an analysis by readsludge.com.

The unions donated a total of $784,000 to Cuomo’s campaign coffers, the report said.

The New York State Building & Construction Trades Council—the umbrella group for 200,000 unionized construction workers — and its locals donated about $137,000.

A political action committee for the Building and Construction Trades Council of Greater New York donated another $140,000.

The opening of the bridge has been a source of controversy.

Cuomo held a splashy press conference last Friday — just days before Thursday’s Democratic primary — announcing the opening of the east-bound span. The westbound section opened last year.

The governor arrived behind the wheel of a 1932 Packard convertible that belonged to Franklin D. Roosevelt when he was governor.

The lanes on the new bridge were supposed to open Saturday, but it was postponed after workers discovered structural issues with the old bridge that threatened the new structure. The entire bridge finally opened Tuesday night after the safety alert was lifted.

Critics charged Cuomo and the New York State Thruway Authority jeopardized public safety by rushing the opening to boost the governor’s re-election bid against Cynthia Nixon.

The New York Times obtained a memo showing Thruway Authority officials offering incentives for contractors to complete the project more quickly.

But Cuomo and Authority officials insisted the contractual opening date was always set at Aug. 15.

Cuomo campaign spokesperson Lis Smith responded: “There is not a single sane person who believes that we didn’t need a new bridge but only this governor was able to get it done. The Governor has always been a champion of working men and women and we’re proud of our work with the building trades to rebuild New York’s infrastructure something that Trump and other politicians have given lip service to but never actually accomplished.”