Dr. Abdul El-Sayed of Michigan is the first Democrat running in a battleground Senate race to publicly call for a pause on artificial intelligence development.

© Nick Hagen for The New York Times

Dr. Abdul El-Sayed of Michigan is the first Democrat running in a battleground Senate race to publicly call for a pause on artificial intelligence development.

© Nick Hagen for The New York Times

High diesel costs have posed a problem for Republicans in the midterms, but President Trump’s decision did not satisfy some candidates in key Senate races.

© Emily Elconin for The New York Times; Doug Mills The New York Times