A South Boston Democrat blocked a proposal from Mayor Michelle Wu that would shift more tax burden onto the commercial and business sectors a day after city officials said they had started circulating key data to lawmakers on property valuations in Boston.

For the second time this week, a Boston state senator moved to stall Mayor Michelle Wu’s proposal to hike commercial property tax rates stalled, arguing that the city’s estimates on the potential increases homeowners could face are “far off” from Wu’s earlier,

Boston Mayor Michelle Wu’s plan to temporarily increase commercial property taxes has stalled again after new data indicated the impact from slumping office building values on the city’s tax system won’t be as stark as initially estimated.