Voting results in my precinct

I have lived in Precinct 0200 of Harris County since summer 2000, and I was surprised by the voting shift between the November 2000 election and the November 2004 one:

2000           2004 PRESIDENT Republican           51.1%          46.2% Democratic           42.7           52.6 Naderite              5.5            0.4 Libertarian           0.1            0.7 HOUSE OF REPRESENTATIVES Democratic           50.3%          48.1% Republican           46.2           47.5 Libertarian           3.5            2.1

(The precinct boundaries were the same in each election.)

I had been under the impression that the precinct was trending Republican, so the 15-point swing in margin to the Democrats in the presidential race surprises me. Have I been misreading what all the new townhouses mean?

And then compare the 15-point Democratic swing in the Presidential race to the 3-point Republican swing in the House race, which puzzles me even more. Precinct 0200 has moved from Sheila Jackson-Lee's district to John Culberson's district. Jackson-Lee is not well-liked, and I would have thought that a lot of people who hadn't voted Democratic before because of her would start.

Can any of y'all help me understand what's going on?