Even Republican strategists were surprised by how few GOP House members voted against the ambitious budget plan from Rep. Paul Ryan, R-Wis., when it reached the floor on April 15. With a 25-seat majority, Republicans could offer vulnerable members a pass. Just before the vote, leaders of the National Republican Congressional Committee say they had anticipated that at least a dozen members from swing districts might take the opportunity to distance themselves from a politically combustible proposal that, among other things, would end Medicare as it now exists for Americans younger than 55.

But just four Republicans voted no, and only one of them, David McKinley from West Virginia, represents a truly competitive district. (The others — Walter Jones of North Carolina, Ron Paul of Texas, and Denny Rehberg of Montana — all hold safe Republican terrain but had idiosyncratic reasons for opposing Ryan.) It was a striking statement of partisan unity, and a moment that revealed the stark contrast in the parties' political strategies.

The nearly monolithic support for Ryan's plan continued a pattern: On this year's biggest votes, almost all Republicans from swing districts have repeatedly sided with their colleagues from more reliably conservative territory. Every House Republican — including all 61 who represent districts that supported President Obama in 2008 — voted earlier this year to repeal the president's health care reform law. The GOP members present likewise voted, unanimously, to bar the Environmental Protection Agency from regulating carbon emissions linked to global climate change. All but seven House Republicans (six from districts that supported Obama) voted to defund Planned Parenthood.

That's a very different calculation than swing-district House Democrats made over the previous two years. In particular, the 48 House Democrats who represented districts that preferred John McCain in 2008 routinely dissented while their side controlled the House last term. Most of those McCain-district Democrats voted against the 2009 bill to limit carbon emissions with a cap-and-trade system, and a majority also opposed the health reform law; 17 voted against both bills. "We have a different type of caucus," Democratic pollster John Anzalone says. "If you are a Democrat, one of the things you do admire about Republicans is their loyalty on [difficult] votes."

It's hard to imagine what might strain that instinct more than Ryan's budget. It overflows with politically incendiary ideas — none more volatile than ending the existing Medicare program for Americans under 55 and replacing it with a voucher (or "premium-support") system that would provide a fixed stipend to purchase private insurance. By including that plan in a budget that simultaneously would reduce the top income-tax rates, House Republicans also allowed Obama to charge, as President Clinton effectively did in his 1995 confrontation with the GOP, that Republicans are unraveling Medicare to fund tax cuts for the rich. And the House GOP took these political risks fully aware that the Democratic Senate would shelve Ryan's blueprint.

Yet none of those considerations fractured their unity. "This is the fight they want to have," says Rep. Tom Cole, R-Okla. Of the 62 Republicans who won 55 percent of the vote or less in 2010, only McKinley voted no. Sixty House Republicans from districts that supported Obama in 2008 backed Ryan on the budget (the other was absent). Republicans now hold 145 of the 231 House seats in which the senior share of the population exceeds the national average of 12.9 percent; all of those members except Jones, Paul, and Rehberg also voted for the budget.

National Journal

The intersection of these data points may represent a kind of bull's-eye for Democrats in 2012. Twenty-one House Republicans, 18 of them freshmen, won with 55 percent of the vote or less last time in districts that voted for Obama in 2008 and also contain more than the national average of seniors; all 21 of those members supported the Ryan bill. Although redistricting could change things, many of these Republicans — such as freshmen Dan Benishek in Michigan and Allen West in Florida — will likely top the 2012 Democratic target lists. (Democrats already hit nine of those 21 this week in a radio ad about the Ryan vote.) Anzalone, at the vanguard of Democratic optimism, believes that the Medicare provisions in the Ryan budget alone could allow his party to recapture the House. "The Ryan budget is the game-changer," he insists.

Given the risks, why did House Republicans lock arms so tightly around Ryan? Fear of tea party primary challengers could be one reason; ideological commitment is another. But as a purely political calculation, trying to demonstrate independence by breaking from the party on key votes doesn't appear to be as effective an electoral strategy for House members as it once was. Today's increasingly parliamentary politics is producing more wave elections in which voters shift between the parties en masse, almost regardless of a member's individual record. Democrats last fall, for instance, lost 11 of the 17 seats held by McCain-district representatives who opposed both the health care and climate-regulation bills.

In that environment, it may make more sense for even vulnerable members to help build a party-wide record of accomplishment than to strategically dissent. "Increasingly, I think members see their fate as being tied to that of their party and less about their own individual relationship with their districts," notes political scientist Alan Abramowitz of Emory University. As a long-term proposition, that's surely correct. But with the GOP now heavily dependent on votes from seniors, the Ryan budget will test whether hanging together can truly reduce the risk of hanging separately for the headstrong new House Republican majority.

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