The question they face now is whether they can turn those advantages into seats.
A review of the 66 districts that flipped from Democratic control to GOP control after the 2010 elections shows that Republicans have emerged with a better map than they had before redistricting, but in many cases, those improvements were slight. Most Republicans who were vulnerable before will continue to be at risk over the next decade.
Despite the GOP’s unprecedented control over the drawing of new lines, there is little room to grow. The party’s big majority makes creating new seats to win much more difficult. There are only so many ways to redraw a map, and Republicans had more incumbents to protect.
The Washington Post has projected that both Republicans and Democrats have come away with about the same number of new districts that they should be able to capture — a result that has led some to declare the 2012 redistricting process a wash.
But that’s only one part of the equation.
The other part is where the GOP’s real advantage lies: in improving on the districts it already controls, or “shoring up” its incumbents.
“They’ve done a great job,” said former congressman Thomas M. Davis III (Va.), who oversaw the GOP’s last redistricting cycle, in 2002, as chairman of the National Republican Congressional Committee.
Davis said that even the slightest changes can be a big help: “You drive off a lot of opposition. Then after that, on election day, maybe you win by a few thousands votes.”
A review shows that many of the changes made for this year’s vote have indeed been minor.
Of the 66 districts that switched from Democratic to Republican after 2010, Republicans were able to redraw 37, while Democrats got to redraw nine.
Of the 56 districts that have been redrawn, more than half (32) became more Republican-friendly, 14 districts got more difficult for Republicans, and the remaining 10 districts basically will stay the same.
A further breakdown shows that although most of the districts will become better for the GOP, the difference is often pretty minor. Of the 32 districts that become more Republican, about half (15) will become only 1 percent or 2 percent more so, and only 10 will become at least 5 percent more so.
Similarly, more than half of the districts that become more Democratic will be only 1 percent or 2 percent bluer.
In the end, 35 of the 56 districts that have been redrawn will change by 2 percent or less — a strong sign that these Republicans will continue to have to watch their backs in November, even if most of them are safer.