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.

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.

Anti-government protests in Russia are taking many different forms, from mass rallies and marches to defiant street art and music.

Just recently, members of a feminist punk group were arrested in Moscow's Red Square after they performed a song ridiculing Prime Minister Vladimir Putin. The group, which calls itself Pussy Riot, says it's planning more stunts before March's presidential elections.

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.

Brian Sella and Mathew Uychich of the New Jersey band The Front Bottoms have been playing together for years.

CNN's political commentator Roland Martin has been suspended, because of tweets sent out during the Super Bowl that organizations like GLAAD called homophobic.

NPR's David Folkenflik reports that the network was also reacting to online criticism of Martin. David filed this report for our Newscast unit:

Most moms probably don't want their babies around pot growers, but San Francisco-based writer-photographer Lisa Hamilton is totally cool with it.

In fact, her baby, Ada, is a little over a year old and has probably already seen more of California than most Californians. And that, to Hamilton, is a problem.

For her, the basic issue is exemplified by something like this: We can see what a stranger in Japan is having for lunch on Instagram. But we can't so easily see where that lunch came from, or who harvested the ingredients.