Rival Democrats and came within a foot of each other just before President Bush's State of the Union speech Monday night and managed not to acknowledge each other, and certainly not touch.
Clinton, clad in scarlet, crossed the aisle between their seats on the House floor. Sen. Edward M. Kennedy, the Democratic icon who had endorsed Obama earlier in the day over Clinton, reached out his hand when she came close.
She took it; they shook. Meanwhile, Obama, dressed in a dark suit, had turned away.
The rivals then retreated to their seats, only the aisle and four senators between them.
It was the latest chapter in the increasingly nasty fight between the two leading candidates for the Democratic presidential nomination and capped a dramatic day.
Hours earlier, Obama received the endorsements of Kennedy and Caroline Kennedy, the brother and daughter, respectively, of President John F. Kennedy. They were joined by Rep. Patrick Kennedy, D-R.I., the senator's son.
The only Republican senator still running, of Arizona, skipped the address to campaign in Florida.