From Eric Dondero:

Numerous Democrats from state legislators to county commissioners have switched to Republican in the last two years. The Dems haven't had much luck in doing the same.

From the Burnt Orange Report, by Keith Hampton, Austin Attorney, Oct. 12 "Turned a Republican into a Democrat... Almost":

For over a year, I have worked tirelessly to persuade Republican Judge Larry Meyers to become the first statewide Republican to switch parties. I was so convinced he would run against Presiding Judge Sharon Keller as a Democrat, I decided to run in an open seat to ensure we had a Democratic candidate in each race. But after weeks of meetings at Texas Democratic Party offices, it recently became clear that Judge Meyers would remain a Republican.

Sidenote; Democrats were successful most recently in persuading Carolyn Crist wife of former Florida Gov. Charlie Crist to become switch.