THIS ONE IS PRETTY EASY TO EXPLAIN. Republicans lost the House and probably the Senate because of Iraq, corruption, and a record of taking up big issues and then doing nothing on them. Of these, the war was by far the biggest factor. Unpopular wars trump good economies and everything else. President Truman learned this in 1952, as did President Johnson in 1968. Now, it was President Bush's turn, and since his name wasn't on the ballot, his party took the hit.

The defeat for Republicans was short of devastating--but only a little short. The House seats the party lost in New York and Connecticut and Pennsylvania will be hard to win back. Just as Republicans have locked in their gains in the South over the past two decades, Democrats should be able to solidify their hold on seats in the Northeast, as the nation continues to split sharply along North-South lines.

What should worry Republicans most, however, is erosion of its strength in the West and in two states in particular: Colorado and Arizona. Fours years ago, Colorado was solidly Republican. Since then, Democrats have won a Senate seat, two House seats, the governorship, and both houses of the state legislature. At the state level, that's realignment.

In Arizona, Republicans dropped two House seats and Republican Senator John Kyl got a mild scare. Kyl, by the way, may be finest and most able senator in Washington. He's certainly in the top five. Meanwhile, Democratic Governor Janet Napolitano cruised to victory.

The bottom line is this: Colorado and Arizona may not be there for Republicans in the 2008 presidential race. Of course, everything depends on the actual candidates, but these two states start out as presidential swing states. This is a new development.

Virginia is now worrisome for Republicans, even if Senator George Allen wins reelection via recount. It has become more a middle Atlantic than a Southern state, as University of Virginia professor Larry Sabato notes. (Sabato, by the way, picked the outcome in the House and Senate almost perfectly.) Republicans have lost the Washington suburbs of northern Virginia, which have grown into a third of the state's vote. And Representative Thelma Drake almost lost her House seat in the Norfolk-Virginia Beach area, a Republican stronghold heavily populated with active duty and retired military.

Already the wails of the immigration restrictionists are rising, insisting Republicans lost because they weren't tough on keeping illegal border-crossers out. Not true. The test was in Arizona, where two of the noisiest border hawks, Representatives J.D. Hayworth and Randy Graf, lost House seats. Graf lost in a seat along the Mexican border, where illegal immigrants flock.

What Americans want is a full-blown solution to the immigration crisis. And that will come only when Republicans come together on a "comprehensive" measure that not only secures the border but also provides a way for illegals in the United States to work their way to citizenship and establishes a temporary worker program. If Republicans don't grab this issue, Democrats will.

Immigration was a big failure of Republicans over the past two years, but hardly the only one. Republicans cast themselves as the party of reform, but they didn't reform anything. And heaven knows, the public is eager for a lot to be reformed, starting with Congress itself and moving on to taxes and entitlements.