Republican presidential candidate Mitt Romney's losses on Tuesday, while not very meaningful in the race to accumulate delegates, have raised questions once again about his ability to inspire passion from his party's base and about his viability in the general election.

Rival Rick Santorum's victories in Colorado, Missouri and Minnesota dealt a setback, if not exactly a body blow, to Romney — whom Santorum routinely dismisses as a candidate with a big machine but no core.

Ask Detroit teachers about their biggest challenge and many will say, "You can't teach kids who don't come to class." Last year, the average Detroit public high school student missed at least 28 days of school.

Now, as part of its effort to get parents more involved, the district has launched a major initiative to improve attendance. The effort includes parent workshops and attendance agents charged with pushing parents to send their kids to school every day.

The band Novalima is undeniably Peruvian, but the music on their new album Karimba is infused with sounds from around the world including dub, salsa and club music.

In honor of Tuesday's delegate-free caucuses and primary, NPR is launching a 2012 Delegate Tracker.

Dolphins have been stranding themselves along the shores of Cape Cod, Mass., since the Pilgrims' times, and this winter is no different. What is different is how long the latest round of strandings has lasted — almost a month. So far, rescuers have counted 147 strandings and 38 successful rescues and releases.

While Rick Santorum won Colorado along with two other states last night, he did not win the key Colorado county of Arapahoe.

Political experts say Arapahoe has been on the winning side in nearly every presidential election of the past four decades.