The presidential primary season may be over with President Joe Biden and former President Donald Trump heading for a rematch, but several down-ballot races are up for grabs that will determine control of Congress. Ohio’s primary on Tuesday will decide which Republican takes on Democratic incumbent Sen. Sherrod Brown in November, as well as congressional contests key to the GOP House majority. This series, Buckeye Blitz, will examine the politics behind the races and the issues that will drive 2024 turnout. Part One, below, looks at how the Ohio Senate primary represents the stark choices fa …