Lt. Gov. David Dewhurst pulled in the most votes among Republican U.S. Senate candidates in the May 29 primary, picking up 624,170 votes (44.6 percent). But his total was more than 70,000 votes short of preventing a runoff with former Solicitor General Ted Cruz, who received 479,079 votes (34.2 percent).

Ahead of the July 31 runoff, both candidates will be vying for the favor of the 21 percent of the primary voting block that chose candidates other than them — if those voters show up to submit a ballot at all.

The largest "not-Dewhurst-or-Cruz" voting block belonged to former Dallas Mayor Tom Leppert, who received 186,675 votes (13.3 percent). Despite efforts by Dewhurst to attack Leppert in the days leading up to the primary, Leppert still had a solid showing in the part of the state that knew him best, namely Dallas County (23,201 votes), Tarrant County (21,814), Collin County (12,640) and Denton County (9,575), valuable votes that played a role in preventing an outright Dewhurst victory.

Below, we have prepared a map that displays by county where Dewhurst or Cruz secured a majority or plurality of the votes. In this case, "majority" means the candidate received more than 50 percent of the vote, and a "plurality" means the candidate only received the most votes. Click on a county to see the vote breakdown, including the number of registered voters, total votes and turnout percentage.