From Jake Tapper:

While he refused to answer most questions about the close Massachusetts Senate race, White House press secretary Robert Gibbs today acknowledged that President Obama “was both surprised and frustrated” with how hotly contested the Bay State special election has become.
Gibbs said he would wait until tomorrow to discuss the results of the election, but said the president was “not pleased” with how much the Democratic candidate, attorney general Martha Coakley, is struggling.
He said the White House didn’t need a special election to note the “tremendous amount of upset and anger” among voters about “where we are economically… In many ways we’re here because of that upset and anger.”