It's not exactly good cop/bad cop, but the main speakers Tuesday night at the Republican National Convention will play diametrically opposed roles.

Ann Romney — the wife of Mitt Romney, who becomes the official GOP nominee with Tuesday's delegate roll call — will try to present her husband in the most flattering, personal light. By contrast, New Jersey Gov. Chris Christie, the convention's keynote speaker, will have the job of attacking President Obama's record.

The Obama administration announced new fuel efficiency standards that require cars in the United States to average 54.5 miles per gallon by the year 2025.

As the Detroit Free-Press reports, President Obama got this process rolling in 2010, when he asked the EPA and the National Highway Traffic Safety Administration to come up with standards that would lead to new and cleaner cars on the roads.

The nation's foreclosure crisis rarely is mentioned by the presidential candidates, but it looms large as their campaigns grapple with finding evicted voters in swing states.

Organizers are discovering scores of vacated homes in key battlegrounds that contributed strong turnouts in the 2008 election. In the past four years, more than 3.7 million homes have been lost to foreclosure, according to market research firm CoreLogic.

Isaac is headed toward the Gulf Coast, and Louisiana's governor has declared a state of emergency. The storm is threatening to hit New Orleans as the anniversary of Hurricane Katrina approaches. Host Michel Martin speaks with Lt. Col. Jerry Sneed of Homeland Security in New Orleans, about how they're preparing the city for the storm.

The GOP's proposed platform supports a federal ban on same-sex marriage. But gay and lesbian Republicans say the party is changing. Host Michel Martin checks in with two Republicans making their issues more visible at the convention: R. Clarke Cooper of the Log Cabin Republicans and Sarah Longwell of Young Conservatives for the Freedom to Marry.

Saying that "it's offensive to me as a woman and as a minority" that Democrats portray the GOP as "the party that hates you" when they reach out to non-whites, South Carolina Gov. Nikki Haley made the case this morning that it's the Republican Party that minorities should be looking to join.

With the Todd Akin controversy barely in the rear-view mirror, another Republican senatorial candidate is causing some waves of his own.

If men could become pregnant, they'd probably visit the doctor more often.

But without a compelling inducement like contraception to get them in the door, they often miss out on sexual and reproductive health services that could protect not only them but also their partners.

There are lots of ways to get to 270 and they don't all involve Florida's 29 electoral votes, according to Rich Beeson, the national political director for the Mitt Romney Campaign.

Beeson, speaking with Morning Edition host Steve Inskeep on Tuesday, says the Sunshine State would be nice to have in the red column, but it's not a sine qua non for clinching victory in November.