The Russell 2000 (NYSEArca: IWM) small-cap index was up more than 3 percent this afternoon, as investor sentiment in small-caps was buoyed after Treasury Secretary Tim Geithner unveiled a financial plan to the House Financial Services Committee that outlined the Obama administration’s proposal for an exhaustive overhaul of financial regulations.

Among the big winners was our Buzz Stock of the Day, Republic Airways Holdings, Inc. (Nasdaq: RJET).

The Indianapolis-based airline holding company just acquired 50 percent of Hawaiian airline, Mokulele. Republic paid roughly $3 million in cash, and coverted $3 million of its $8 million loan to Mokulele, for a 50 percent stake in the company.

Republic Airways Holdings also owns Chautaqua Airlines, Republic Airlines and Shuttle America, and offers scheduled passenger service on 1,300 flights daily to 104 cities in 36 states, Canada, Mexico, and Jamaica.

In September 2008, Midwest Airlines hired Republic Airways Holdings Inc. to operate Midwest Connect flights previously flown under the Midwest Airlines name. The move came after Republic agreed to provide up to $25 million in financing to Midwest, which helped prevent a Chapter 11 bankruptcy filing.

We like RJET because we think it’s a resilient company. Despite a huge downturn in travel, Republic’s has only shed 3 percent in it’s year-over-year quarterly revenue growth–substantially less than competitors ExpressJet Holdings, Inc. (NYSE: XJT) (-63.2 percent), Mesa Air Group, Inc. (Nasdaq: MESA) (-18.8 percent) and SkyWest, Inc. (Nasdaq: SKYW) (-13 percent). Republic Airways Holdings also has a healthier operating margin than most of its competitors, and earned about $84 million, or $2.40 a share on revenue of$1.5 billion.

RJET shares have taken a beating this year, like most other airline stocks. Shares are down almost 80 percent and trade near their 52-week low.