Final answer:
The two states with the highest positive increase in population from 2000-2004 are likely California and Texas, based on their significant Hispanic population growth and their large share of US population growth since 1990.
Step-by-step explanation:
The two states that had the highest positive increase in population from 2000-2004 are not explicitly stated in the provided references. However, taking into account that nearly half of the Hispanic population lives in California or Texas, and there has been a significant increase in the Hispanic population outside of those states especially in the South, it can be inferred that California and Texas might be the two states with the highest population increase during that period.
Additionally, another reference mentions that California, Texas, and Florida accounted for about one-third of the entire US population growth since 1990, further suggesting California and Texas as likely candidates for the highest increases from 2000-2004.