A businessman at his core, Mitt Romney was legendary in the private sector for his reliance on reams of information and extensive research to decide which companies to take over.
When interviewing potential employees, he favored question-and-answer sessions designed to make recruits think on their feet and provide clues about how they approached situations.
"I like gathering data and information so that you don't just have people just expressing their opinions, but you actually have numbers and facts and figures and people to look to and to find out what's really happening," Romney told C-SPAN recently. "And then with the information you have, you make the decision."
Now, as the Republican presidential candidate weighs a running mate, it's a good bet that he's relying on that same methodical approach and interviewing style that he honed at Bain and Co. and the private equity firm he helped start, Bain Capital. The style even has its own name: The Bain Way.
"This is going to be a very long process. A lot of information is going to be involved," Romney adviser Kevin Madden said recently, though he was quick to add, "Ultimately it comes down to a one-man decision."
Judging by Romney's record when it comes to business and personnel choices, it's a process that could prove challenging for any of the prospective vice presidential nominees he scrutinizes.
Not that Romney or his team rush to talk in public about who those people are or how close he is to making a decision. On Tuesday, Romney was forced to make a rare on-camera statement that his team was considering Sen. Marco Rubio as a running mate. His statement in Holland, Mich., sought to quiet outrage over reports that the promising Cuban-American from crucial swing state Florida was not getting a proper consideration.
The hush-hush nature of the search partly reflects how Romney used to do business in his decades in the private sector. Much like when Romney's team investigated a company for a potential takeover, his political aides are trying to be discreet as they cull public records and prepare to start whittling a short list before presenting their boss with a final recommendation for a running mate.
The most Romney has said about his search for a No. 2, the biggest decision he'll make before the election: Being prepared to be president is his top criterion.
That factor and the methodical selection process run counter to how 2008 GOP nominee John McCain chose the untested Alaska Gov. Sarah Palin as his running mate. Palin was a risky selection that raised questions about McCain's decision-making.
Obama went with Joe Biden, a veteran senator who twice had run for the White House and had been screened thoroughly.
Eight years before that, George W. Bush choose a Washington veteran in Dick Cheney, a former congressman, White House chief of staff and defense secretary who initially was in charge of finding Bush a running mate.
Romney's search is well under way and Republican insiders suggest an announcement could come as early as next month.
His years in business shed light not just on how he's running his campaign, but also on how he may behave in the White House.
Those who worked with Romney in the 1970s, 1980s and 1990s at the Boston-based firm describe a savvy executive who arrived to meetings armed with tons of information he would study before making decisions. They talk of a leader who oversaw thousands of detailed interviews as he considered whom to hire. All this, they say, still is referred to as The Bain Way.
"The whole process is very methodological," William Oliver, who worked directly for Romney at Bain and Co. in the 1980s and now teaches at Brandeis International Business School. "It's numbers and it's analysis."
When it came to big decisions about what companies to take over, every trait was measured on a scale, every answer in an interview assigned a numerical value and every variable considered over and over. There was no room for a gut feeling or a hunch when choosing whether to invest in a company. If the numbers didn't work, Romney's team usually wouldn't gamble on an investment.
The results made Bain a top-tier brand and Romney wealthy.
Bain Capital invested about $2.5 million in the early days of Staples. The first store opened in 1986 and, when the chain went public three years later, Bain pulled in $13 million. Bain turned a $5 million investment in Accuride's tire rim line into a $121 million boon.
But there were failures, too. Bain lost most of its $2.1 million investment in a bathroom fixture company and saw a handbag company fail after a $4 million investment.
When choosing employees, Romney's team put applicants through a series of questions designed to test quick thinking and critical analysis.
What is the revenue of a London music festival? How can Bain help a European airline turn around its declining profits? What would an applicant do if he didn't get a second interview?
It wasn't that the interviewers expected applicants to know how many taxis were actually in New York City. Rather, they wanted to see how the applicant would figure out an answer on the fly.
"We're talking very analytical attention to details, we're talking about a deep dive into the operations of a company," said Howard Anderson, a senior lecturer at MIT's Sloan School of Management who has studied both Bain and Romney. "By the time Bain makes an investment, they know more about the company than the company knows about itself."
Romney will end up knowing just as much about his running mate.
He has spent a considerable amount of time studying the benefits and drawbacks of potential candidates such as Rubio, Ohio Sen. Rob Portman and New Hampshire Sen. Kelly Ayotte. Others who may be in the mix include New Jersey Gov. Chris Christie, former Florida Gov. Jeb Bush, Rep. Paul Ryan of Wisconsin and Virginia Gov. Bob McDonnell.
Data and research are driving the weeding-out process for the rest. Tough interviews with Romney are all but certain to follow for those who make the cut.
"My criteria is: Who can be president if that were necessary?" Romney told the Des Moines Register this week.