Primary elections set up major Senate fights in Texas and North Carolina, and they also expose fresh tension over voting rules. North Carolina locked in a high-stakes matchup as Democrat Roy Cooper faces Republican Michael Whatley. The race helps decide Senate control in November. In Texas, Sen. John Cornyn heads to a May 26 runoff against Ken Paxton. Big money keeps flooding the contest. Voting also turned chaotic in Dallas and Williamson counties. New precinct rules confused voters and triggered lawsuits.
