Senate Democrats Slim Majority May Soon Get Even Smaller

Senate Democrats could see an even slimmer majority than the already-razor-thin edge they hold right now as a key swing member of their caucus considers leaving the party.

Senator Joe Manchin of West Virginia is "thinking seriously" about switching his party affiliation from Democrat to independent, threatening to bring down the number of Senate seats held by Democrats from 48 to 47. Republicans currently hold 49 Senate seats, but with three independent senators who all caucus with the Democrats, the Democratic Party still holds a narrow majority.

Asked about becoming...