National and World News from NPR

(Revised at 2:03 pm ET with new Ron Paul-Pennsylvania material.)

The contest for the Republican presidential nomination may be over for all practical purposes, with Mitt Romney the all-but-certain GOP nominee. But that doesn't mean there's nothing of interest in Tuesday's primaries.

Voters are going to polls in Pennsylvania, Rhode Island, Connecticut, Delaware and New York, though turnout is expected to be low. Still, here are four things to watch for.

I have to admit I was a bit reluctant when I first saw this series of "Bicycle Portraits" because biking has, in some cases, become something of a cliche steeped in hipdom sprinkled with granola. Or mainly: For NPR to present a series of bicycle portraits just seemed too cute, too predictable.

"The first criminal charges in connection with the BP oil spill have been filed against a former BP engineer named Kurt Mix," NPR's Carrie Johnson reports exclusively.

Carrie just told our Newscast unit that Mix has been charged with obstruction of justice for allegedly deleting text messages after the spill. The texts were related to the amount of oil gushing into the Gulf. Mix will make his first appearence in court today.

The Supreme Court will hear arguments Wednesday on Arizona's hotly debated immigration law. The court's decision will affect Arizona and other states that have adopted similar legislation. Host Michel Martin talks with one of its authors, Kansas Secretary of State Kris Kobach, and law professor Gabriel Chin.

As a little girl, Anna Quindlen wasn't afraid of a whole lot. She frequently got into trouble and occasionally shot off her mouth. But as she grew older, the Pulitzer Prize-winning writer became what she calls a "girl imitation."

After a slight decline in March, the widely watched consumer confidence index from the private Conference Board "was virtually unchanged in April," the research group reports.

"The index now stands at 69.2, down slightly from 69.5 in March," it says.

"Overall, consumers are more upbeat about the state of the economy, but they remain cautiously optimistic," Lynn Franco, director of the board's consumer research center, adds in its release.