EXHIBIT 23.1
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            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-4) and related Prospectus of Wintrust Financial
Corporation for the approval of the merger agreement between Wintrust Financial
Corporation and First Northwest Bancorp, Inc. and to the incorporation by
reference therein of our report dated February 13, 2004, with respect to the
consolidated financial statements of Wintrust Financial Corporation included in
its Annual Report (Form 10-K) for the year ended December 31, 2003, filed with
the Securities and Exchange Commission.


                                             /s/ Ernst & Young LLP
                                             ERNST & YOUNG LLP

Chicago, Illinois
January 20, 2005