WASHINGTON (AFP) - Veteran senator Joseph Biden has a key dual role as Barack Obama's running mate: to woo the working class and bring a wealth of foreign policy knowledge to the Democratic White House hopefuls. "Obama made an excellent choice. He is very strong in domestic policy, but is not as experienced in foreign affairs. Biden brings that expertise to the ticket," professor Paul Herrnson at the University of Maryland told AFP. And putting the unknown first time Republican Alaska governor Sarah Palin up against Biden, a veteran senator of 36 years, was in Herrnson's opinion a bad idea. Biden, 65, a veteran senator from Delaware who is wedded to his working class roots, was unveiled as Obama's choice for running mate in late August. An Irish Catholic, Biden grew up in Scranton, Pennsylvania, a former steel and mining town long-affected by industrial decline in the second half of the 20th century. His no-nonsense style and appeal to traditional grass roots Democrats, gives him an edge in connecting with those working class voters who were initially wary of Obama and his unusual background. "Biden is certainly an asset to Obama. He was a very wise choice both because of his extended foreign policy experience and because he is a tough campaigner," agreed Richard Langhorne, a professor at the Rutgers university in New Jersey. "Biden has travelled very widely, has a strong sense of US external interests and is widely believed to be wise on the general topic of foreign affairs."