Obama chats up superdelegates in House

As Obama made his way back down the center aisle, Rep. Ray LaHood, Republican of Illinois, who is retiring after his seventh term, gave chase and grabbed Obama's arm. The senator turned and gave LaHood a hug.

After leaving the chamber, Obama made his way back across the Capitol surrounded by reporters and photographers, pushing forward into the Rotunda as startled tourists realized there was something more exciting to look at than statues and paintings. They cheered and shouted.

As he walked, Obama insisted that the Democratic race would continue. "Senator Clinton is a formidable candidate, she is very likely to win West Virginia and Kentucky; those are two states where she's got insurmountable leads," he said. "There is no doubt that she is the heavy favorite in both states, but my goal has been to spend time in all 50 states."

Obama said his visit to the House was intended partly to reassure Democrats who were concerned about the divisiveness of the long primary contest and also to appeal to potential supporters.

"There are some undecideds," Obama said. "If they have questions for me, then I am certainly happy to respond to them. Obviously people have been anxious about some of the sense of division in the party, and I just wanted to assure them that whatever happens, we will be coming together."

Outside the old Supreme Court chamber, Obama found himself encircled by photographers as members of a tour group shouted at him from across the room. "We're from Illinois over here," someone said.