Our politics reporter Kellen Browning walks through the four Senate races that progressive Democrats are closely watching in the upcoming midterm elections.

The Alaska Supreme Court ruled months ago that two candidates, both named Dan Sullivan, could appear on the ballot on Election Day.

© Christopher S. Miller for The New York Times

© Christopher S. Miller for The New York Times

The department, in a highly unusual lawsuit, argued that confusion over candidates with similar names could taint the election result.

© Doug Mills/The New York Times

The Republican incumbent, Dan Sullivan, and his Democratic challenger, Mary Peltola, veered from serious discussion of high prices and economic challenges to blistering personal attacks.

© Matt Faubion/Alaska Public Media

Slashing personal attacks dominated the first televised face-off between Dr. Abdul El-Sayed, the Democratic nominee for Senate, and former Representative Mike Rogers, his Republican rival.

© Pool photo by Paul Sancya

In one of the nation’s most expensive and closely-watched Senate races,