Actually derailing the redistricting effort, which was one of nearly 20 items added to the special session agenda by Gov. Greg Abbott, would be a herculean lift fraught with risk for legislative Democrats. Delaying the process with a walkout would require strong participation by most of the party's caucus, and could carry steep financial costs.

President Trump has said he wants a "simple redrawing" of Texas' congressional map where Republicans pick up five seats.