Members of the Senate Democratic caucus board buses to take them to the White House for a meeting with U.S. President Barack Obama on the government shutdown and debt limit increase October 10, 2013 in Washington, DC.  - 

A grab bag of 55 tax benefits expired at the end of last year, and Democratic Senator Ron Wyden of Oregon, the new chairman of the Senate Finance Committee, wants Congress to reinstate them.

"Although they all have the same expiration date, that’s the only thing they have in common," says Richard Kaplan, who teaches tax law at the University of Illinois. "There is no coherent theme to this package."

There are tax breaks for Americans who use mass transit, and for businesses that invest in research.

"There are some that, shall we say, have a little bit more narrow benefit," says Gabe Horowitz, with the think tank Third Way. Horowitz points to tax breaks that benefit the owners of thoroughbreds and NASCAR racetracks.

Follow David Gura at @davidgura