Pelosi election-overhaul bill passes without a single Republican vote

House Speaker Nancy Pelosi narrowly secured passage of her signature election-overhaul legislation Wednesday without a single Republican vote, sending the heated debate over how America votes to the Senate where the bill is all-but doomed.

The proposal, which is known as H.R. 1, passed on a 220-210 vote almost entirely along party lines. Although one Democrat voted against the bill, the vote was otherwise entirely partisan, underscoring the gap between the two parties on election laws.

“Everything is at stake,” Mrs. Pelosi, California Democrat, said at a press conference ahead...