Beyond their often spirited repartee in the hearing room, Representative Van Hollen of Maryland was among the most fervent in trying to oust Republicans across the country in the 2012 election for their support of the budget plan championed by the Wisconsin Republican. Mr. Ryan excoriated Democrats' own budget priorities as the GOP's vice presidential nominee.
Yet if Washington is going to find the grand fiscal accord that has proved so elusive, these two longtime antagonists will play a central role. On both the politics and policy of the budget, Van Hollen and Ryan are bellwethers of their respective conferences. As much as any two people in Congress, they would be critical in rallying their colleagues to get a deal that has the tax increases Republicans abhor and the entitlement changes Democrats equally detest.
While their political fights have been intense, the two men harbor a personal affinity and respect for each other, in no small part due to their similar dispositions. Both are amicably wonkish former congressional staffers. Both are rising stars within their own parties – Ryan is a potential 2016 presidential contender while Van Hollen is widely regarded as the favorite to replace House minority leader Nancy Pelosi (D) of California should she retire.
If there's going to be any movement on a "grand bargain" this summer – and signals from the president and leading lawmakers in both parties indicate there will be another attempt to fashion one – many expect the legislation to originate in the Senate. The path to passage there is more clear-cut.
But if such a bill were to land in the House, it would be Ryan and Van Hollen who would shoulder the responsibility for either supporting or sacking it. Rank-and-file members "want to know, is that policy going to work?... It's tough for normal members to know how effective or not effective" any politically uncomfortable grand bargain might be at actually fixing the nation's fiscal problems, says Maya MacGuineas, president of the Commission for a Responsible Federal Budget.
Politically, the two men will play similar roles. On the right, Ryan has been a liaison between the GOP leadership and the party's fractious, more junior base of conservatives on setting a strategy on spending issues. It would almost certainly fall to him to fight for any sweeping fiscal deal among the chamber's most conservative members.
"He's pretty critical in bringing these young guys along because he's respected, and he's been at it so long," says former Rep. Steven LaTourette of Ohio, a centrist who was himself considered a dealmaker in the House.
Van Hollen, too, has carved out a niche as the go-to source for House Democrats on budget issues. "People absolutely turn to him, increasingly, for advice on budget and related fiscal matters," says Rep. Gerry Connelly (D) of Virginia.
But will these two budget warriors reach an accord? Ryan has shown a willingness to make tough calls in the past. He voted for the bailout of financial institutions, has been a longtime sponsor of comprehensive immigration reform, and broke with two of his closest colleagues in the GOP leadership to vote for the year-end "fiscal cliff" tax deal. He recently lunched with President Obama and Van Hollen to discuss financial issues and said his budget was an "invitation" to a broader discussion with Democrats.
"Ryan, within the Republican Party, [has] taken on this image of being the kingmaker both intellectually but also politically," says Julian Zelizer, a congressional historian at Prince-ton University. "In the end, for a real deal or a real drama, you need a 'Nixon goes to China' moment, and he's the one who could do it."
Perhaps boding well for such talks is that Ryan and Van Hollen have already gone through multiple rounds of fiscal negotiations: Both understand all the pressure points. "In some ways, the answer is hiding in plain sight," Van Hollen says. "On the other hand, it's been very difficult to get there."