Pershing Square Capital Management’s William Ackman is a hedge fund manger who puts his money where his mouth is, at least, when it comes to his commitment to retailer Target Corp.

Although a special fund Ackman raised to invest in Target lost almost 90% in 2008, he reportedly has put $25 million of his own money into the fund. In the last quarter of 2008, Pershing Square upped its stake in Target from 9.5% to 9.7%, according to regulatory filings.

Bookseller Borders Group Inc. is another retailer that Ackman is hanging on to. Besides keeping its almost 40% stake in the company, Pershing Square agreed to extend the deadline to purchase Borders U.K.-based gifts and stationery business Paperchase until April 15. The $65 million deal already went past one deadline on January 15, when it was extended until February 16.

One retailer Pershing Square dropped in the fourth quarter of 2008 was Borders’ rival, Barnes & Noble Inc., according to regulatory filings. Barnes & Noble was said to be considered acquiring Borders in the spring of last year after Borders put itself on the block. However, as lending dried up, so did Barnes & Noble’s expansion plans.