“Who is your choice to BEAT Marcy?” That catchphrase for a recent GOP candidate forum in Toledo, Ohio, is also the question that voters along Lake Erie will decide on May 5 in one of the nation’s most-closely watched congressional races. Five Republicans are on the primary election ballot in Ohio’s 9th congressional district; the winner will challenge America’s longest-serving congresswoman, Rep. Marcy Kaptur, in the Nov. 3 general election. The 79-year-old Democrat is running unopposed in her bid to retain the seat she has held since 1983. Last fall, after Ohio lawmakers realigned the district’s boundaries, it changed from a “toss-up” to leaning Republican, according to the University of Virginia Center for Politics....