In the last 10 years roughly 250,000 people from Puerto Rico moved to Orlando according to census figures. This is a big part of why Barack Obama took Orange County by 85,000 votes when John Kerry and Al Gore only took the county by 2000 votes. A large portion of this new community lives in east Orlando and northern Osceola County. This area was made into a District that happens to include Alan Grayson's home. Grayson will apparently be running against Todd Long, a tea party Ayn Randian fruitbat. Long was a constant minor irritant to the establishment repugs so they districted him into the new Grayson district where he can run and lose to his hearts content.
In a last minute move during redistricting they made a minor adjustment to the map to pull Sandy Adams' house out of the Grayson district into Mica's district, which leans strongly republican. She probably asked them to do so because there is no chance she would have beaten Grayson in the new district which leans heavily dem.
In short, I bet she thought her chances were better unseating Mica in a very red district than beating Grayson in a very blue district.
The criticism of Mica is fair, he does specialize in earmarking transportation dollars for the district and has for a very long time. We are getting commuter rail locally, and would have had high speed rail, except Gov. Scott refused the money Mica pulled in for that. Construction businesses like Mica and I am sure went to bat for him financially.