Senator Barack Obama added three superdelegates to his total today, a boost that comes after he saw just a trickle of delegates go to his side in recent days. Despite Mr. Obama’s triumphant speech in Iowa and the buzz about the vice presidential search, the Senator had not initially capitalized on his performance in Tuesday’s primaries, which gave him a majority of pledged delegates. (He received only two superdelegates on Wednesday and none on Thursday).

But the wave seems to be building again today, as Mr. Obama picks up three additional superdelegates – and one is a switch from Mrs. Clinton. Representative Dennis Cardoza of California cited Mrs. Clinton’s signature campaign issue in justifying his change of sides. From his statement:

I am deeply concerned about the contentious primary campaign and controversy surrounding the seating of delegates from Florida and Michigan – two states Democrats need to win in November. I will not support changing the rules in the fourth quarter of this contest through some convoluted DNC rules committee process. Yet, we must find a resolution to seat the Michigan and Florida delegates so these states’ voters are represented at the Convention. I believe we need to avoid this potentially divisive situation by uniting behind one nominee and bringing the party together immediately. Therefore, I have made the decision to support Senator Obama at the Democratic Convention in my role as a super delegate.

Mr. Obama’s campaign also announced the backing of Representative Jim Costa, also of California, and of Jenny Greenleaf, a Democratic National Committeewoman from Oregon.