Nikki Haley for vice president? Let the speculation begin. The governor of South Carolina leapt into the forefront of possible 2016 Republican running mates Tuesday with her address following President Obama's State of the Union speech. And she told NBC's Matt Lauer on Wednesday that while she's not campaigning for the job, she would "sit down and talk" with any candidate interested in her. Among many prospects:

Sen. Rob Portman

Pros: Experience as White House budget director and U.S. trade representative. In 2010, Portman, 60, easily won election to the Senate in the critical state of Ohio. He's considered a thoughtful center-right voice.

Cons: Quiet, unexciting, not conservative enough for the GOP right.

Gov. Brian Sandoval

Pros: Was a federal judge, confirmed 89-0 by the Senate. In 2010, the 52-year-old Sandoval, 52, won the governorship of Nevada over Rory Reid, son of Senate Democratic leader Harry Reid. Easily won re-election in 2014.

Cons: Untested beyond Nevada, and unexciting.

Gov. Susana Martinez

Pros: The nation's first Latina governor, Martinez, 56, made Time magazine's 2013 list of the world's 100 most influential people. New Mexico re-elected her last year.

Cons: The Santa Fe New Mexican reported federal investigators are looking into campaign practices.

Sen. Marco Rubio

Pros: Yes, he's seeking the GOP presidential nomination. But if Rubio, 44, doesn't win, and runs a credible race, he'll get a look for the second spot. He's young, Cuban-American, and from a pivotal state, Florida.

Cons: So far he hasn't gotten much momentum among Republicans nationwide.

Sen. Kelly Ayotte

Pros: Ayotte, 47, is respected in the Senate as a thoughtful voice on national security matters. Won a Senate seat in the swing state of New Hampshire.

Cons: Not a strong public speaker and faces a tough re-election campaign this year.

Sen. John Thune

Pros: A Republican hero because he beat Senate Democratic leader Tom Daschle in South Dakota in 2004. Part of Republican Senate leadership, the 55-year-old Thune is known as steady, thoughtful.

Cons: From a small state, doesn't create much campaign excitement.

Haley: There are lots of reasons Haley, 43, makes sense. Southerner. Daughter of Indian immigrants. Her party needs help winning women voters. Second-term governor. Showed lots of grit last year when she led the move to remove the Confederate flag from the Statehouse grounds. Of course, this all assumes there's logic involved in picking a running mate. And there often isn't. Tribune News Service