Monday's Financial Winners & Losers

New York Stock Exchange (NYX Quote) climbed more than 4% after the Dutch government gave its crucial backing to the Big Board's planned $14 billion merger with Europe's Euronext exchange. Shares were trading up $4.20 to $102.25.

Citigroup (C Quote) surged after a Merrill Lynch analyst upgraded the bank to a buy from a hold. The analyst predicted significant 2007 revenue growth stemming from lower interest rates and said that Citigroup harbors less deal risk than its peers. Shares were up $1.03, or 1.9%, to $55.10.

MidSouth Bancorp (MSL Quote) gained after the Louisiana-based bank said it would pay a special dividend of 3 cents a share, along with its regular quarterly dividend of 6 cents. Shares were up $1.89, or 6.2%, to $32.50.

Sovereign Bancorp (SOV Quote) fell after an RBC Capital Markets analysts downgraded the stock to on a downgrade underperform from sector perform. Shares were down 18 cents to $25.46.

First Mercury Financial (FMR Quote) rose on news that the insurer had been added to three Russell stock indices as of the close of trading on Dec. 15. Shares were up 49 cents, or 2.2%, to $22.58.