Hours before he and President Barack Obama were due to be sworn in for their second four-year terms, Biden told supporters at the Iowa State Society inauguration ball late Saturday: “I’m proud to be president of the United States.”

The audience laughed and then cheered. Biden’s son Beau, Delaware’s attorney general, interrupted his father and told the crowd he had misspoken…

Showing appreciation to Iowa, an industrial and farm state that is home to 3 million people, is an expected courtesy in national politics because of the state’s role in separating contenders from pretenders in each presidential race.

In early 2008, the results in the Iowa caucuses convinced many Democrats the Obama could win the Democratic nomination over former first lady Hillary Rodham Clinton, now Obama’s secretary of state.