It looks like the Republican leadership is starting to wrestle with the problems inherent in their promise to find a way to balance the budget over 10 years with all their spending cuts. In particular, it turns out that they might need to cut spending on programs that benefit people who are old right now.
Here's the basic dilemma: Normally when Republicans want to cut spending they want to cut it right away. Sequestration reduces the amount of money available to provide healthy food to low-income pregnant women and their newborn children right now. And that's the part of sequestration Republicans like. They want to replace the part that cuts spending on the military with immediate reductions in other spending designed to boost the living standards of poor people. But the government's biggest domestic programs—Social Security and Medicare—are targeted at the elderly, and since older cohorts are whiter and more intolerant of gays and lesbians the core of the GOP electoral coalition is older Americans.
Consequently their recent budgets have included important exceptions to the principle of spending cuts right away. Their promise is that if you're getting Social Security or Medicare today, your benefits will never be reduced by one red cent. In fact, your benefits will never be cut as long as you're lucky enough to have been born before 1958. The idea is that someone who's 57 today can vote Republican, see Paul Ryan's budget pass, and then be relaxing thirty years from now at the age of 87 still enjoying full Social Security and Medicare benefits.
It's a sweet deal, but it means that the cuts to the parts of the budget that aren't Social Security and Medicare would have be really extreme to balance the budget within 10 years. Looking it over, Ryan is reportedly coming to the conclusion that he might need to trim the scope of that exemption from cuts and make people born in the mid-fifties bear some pain. This is—rightly—making Republicans from more marginal House seats nervous. The politics of present-day conservative budgeting hinge entirely on persuasiding old people that draconian cuts to programs for old people can be implemented without taking anything away from the people who are already old. Anything that calls that into question is very dangerous.