Rep. Paul Ryan has made his reputation as a numbers man, a wonk whose expertise has been in the dry details of budgets, the country's fiscal path and entitlement reform.
But the Wisconsin Republican has taken on an entirely new quest: immigration reform.
It's an issue fraught with emotion. It's a passionate battle over securing the border, welcoming newcomers to an economy in which millions of Americans are already scrapping for work, and deciding whether those who entered the U.S. illegally should be offered a pathway to legalization.
There's no pie chart in the world that comprehensively explains the abstract values that underpin efforts to change the American immigration system.
But Paul still thinks numbers will ultimately be the key to unlocking differences and, after years of futile effort, settling on a solution to which both parties can agree.
Immigration, he says, ticking off statistics, is about the economy.
"I always look at this as an economics issue," he told the Washington Examiner. "In 2010, the last year we have statistics -- I think I can do this off the top of my head -- something like 72 percent of the visas were granted to relatives, 7 percent for economic visas. We need an immigration system that's more wired to give our economy the labor it needs to grow faster."
In taking on immigration reform, the congressman is treading unknown waters. His success or failure may determine whether he remain the House's foremost fiscal wonk, or a major political player capable of influencing Republican votes on a range of policy issues.
Ryan compares his mission now with his efforts to convince the GOP to support his 'Path to Prosperity" budget proposal. "Getting Republicans on the third rail was no small task," he said, referring to the Social Security and Medicare reforms in his budget proposal. "It took me about four years to do that."
And with the 2012 presidential campaign behind him, the former vice presidential nominee argues that he now has the clout to move beyond his traditional domain of budgetary issues.
"The campaign ended up serving me the ability to do more with my job," he said.
Ryan is quick to dismiss the comparison with Sen. Rubio, R-Fla., who played a leading role in the Senate immigration reform package. The potential 2016 presidential contender is just as quick to slam suggestions that immigration is part of a political calculation -- for himself or for his party.
By Tim Mak
"I learned that lesson early in life: Life is far too short to be worried about losing your job. If you want to be good at these jobs, you have to be willing to lose these jobs," Ryan responds. "I'm not... going to cloud my mind worrying about how this helps position myself politically."
CNN exit polling shows Ryan and Mitt Romney only received 27 percent of the Hispanic vote in 2012, a shortcoming to which many Republicans point as a reason the party must help reform the American immigration system.
"That's a bad reason," Ryan says. "Just because we got whatever percent of the Hispanic vote, that should not be a motivating factor."
Though he'll argue for immigration reform with the same calibrated logic he's used to explain his budget plans, Ryan does understand the issues emotional impact. He cites in his speeches not a person but a poster, a notice once intended to explain America to newly arrived Irish immigrants. It reads:
"In the United States, labor is there the first condition of life, and industry is the lot of all men... In America, a man's success must altogether rest with himself. It will depend on his industry, sobriety, diligence and virtue; and if he do not succeed, in nine cases out of ten, the cause of the failure is to be found in the deficiencies of his own character."
A friend of Ryan's spotted the poster while touring the Jeanie Johnston, a ship used by immigrants escaping the Irish potato famine.
"You see this thing?" he asks. "The immigration story is the American idea. The melting pot is the American idea... the condition of your birth doesn't determine the outcome of your life."