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Exhibit 23A

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We hereby consent to the incorporation by reference in this Registration Statement on Form S-4 of Mercantile Bankshares Corporation of our report dated March 10, 2006 relating to the financial statements, management's assessment of the effectiveness of internal control over financial reporting and the effectiveness of internal control over financial reporting, which appears in Mercantile Bankshares Corporation's Annual Report on Form 10-K for the year ended December 31, 2005. We also consent to the reference to us under the heading "Experts" in such Registration Statement.

Baltimore, Maryland
May 24, 2006

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CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM