City Councillor Sam Yoon’s top aide in City Hall is moving over to the campaign. Mary Grissom, Yoon’s chief of staff, will be taking over as campaign manager, a campaign spokesman confirmed to the Reporter.

She is leaving City Hall at the end of the week, replacing Scott Sherman atop the campaign.

Previously, Grissom served a board member of Project HIP-HOP for three years and projects coordinator for the Union of Minority Neighborhoods for two years. Sherman had previously worked on a Congressional campaign in Florida.

Yoon is challenging Mayor Thomas Menino for corner office in City Hall, along with City Councillor At-Large Michael Flaherty and South End businessman Kevin McCrea.

The campaign shake-up comes as the four camps gird for the 10 weeks left before the Sept. 22 primary, when two candidates will emerge for the November final election.