It's reasonably close. There are still plenty of Democrats representing districts that Bush won and some Republicans representing districts Kerry won, but not nearly as there would have been in 2000 before the redistricting. Districts that go strongly for one Presidential candidate or the other simply aren't going to support a Congressional candidate of the opposing party, with only a handful of exceptions, like Scott Matheson of Utah.
Here are the 2000 numbers......
In 2000 Bush won 239 of 435 congressional districts, to the Democrats' 196. Yet, in the 107th Congress elected in 2000, the Republicans had a 222-213 majority. That meant that a sizable number of Bush districts elected a Democratic congressman, but it also demonstrated that most Al Gore districts elected a Democrat and most Bush districts elected a Republican.