WASHINGTON—Democrats have come closer than ever to achieving the long-sought minimum wage hike, but opposition grows against the inclusion of a nationwide wage floor of $15 an hour in the forthcoming coronavirus relief package. Small businesses in particular will breathe a sigh of relief if the proposal to increase federal minimum wage fails to pass Congress as part of the economic rescue plan. The federal government last raised the minimum wage to $7.25 in 2009. President Joe Biden’s relief plan includes a proposal to increase the minimum wage from $7.25 to $15 an hour with increases of nearly $1.50 every year for five years. Democratic Senators Kyrsten Sinema of Arizona and Joe Manchin of West Virginia have already expressed concerns about including the provision in the $1.9 trillion relief package. “The minimum wage provision is not appropriate for the reconciliation process. It is not a budget item. And it shouldn’t be in there,” Sinema …