Partners at powerhouse Washington firms Arent Fox and Patton Boggs have been tapped to represent four Republican candidates for the 2012 presidential race.

William McGinley and Benjamin Ginsberg of Patton Boggs were hired by the campaigns of Minnesota Rep. Michele Bachmann and former Massachussetts governor Mitt Romney, respectively.

Arent Fox’s Brett Kappel and Craig Engle will work on campaigns for Texas Rep. Ron Paul and former Utah governor Jon Huntsman, respectively.

The hirings were first reported by Politico.

President Obama will again tap his attorney from the 2008 campaign, Perkins Coie partner and former White House counsel Bob Bauer.

SNR Denton snags Freddie Mac general counsel

Robert Bostrom, executive vice president and general counsel at Freddie Mac, will join SNR Denton as partner and co-chair of the firm’s financial institutions and funds sector. He will start in mid-August.

Bostrom, who began his tenure at Freddie Mac in 2006 and guided the mortgage finance giant’s legal strategy during the financial crisis, previously served as top legal counsel for National Westminster Bancorp and led the Financial Institutions Practice at Winston & Strawn.

Four D.C. firms make top 20 mid-size ranking

Washington-based Beveridge & Diamond, BuckleySandler, Novak Druce + Quigg and Zuckerman Spaeder were among the nation’s top 20 mid-size firms, according to an annual ranking by the National Law Journal.

The 2011 Midsize Hot List, released last week, surveys and ranks firms with 50 to 150 lawyers by looking at big cases and deals, diversity and pro bono work.

Beveridge & Diamond specializes in environment law, BuckleySandler in financial services, Novak Druce + Quigg in intellectual property and Zuckerman Spaeder in litigation.

D.C. Bar taps new pro bono director

Monika Kalra Varma, director of the Robert F. Kennedy Center for Human Rights, has been named executive director for the D.C. Bar’s pro bono program. She will replace the program’s longtime director, Maureen Thornton Syracuse, who is retiring on Sept. 30.

At the RFK Center, Varma oversees day-to-day and long-term operations, budget decisions, fundraising and pro bono participation by law firms. She previously served as the center’s program director and associate legal officer of the U.N. International Criminal Tribunal for the former Yugoslavia.