Hold on, say supporters of the seemingly failed $567 million school bond issue that would fund safety and security upgrades in Jefferson County. The measure, once written off as defeated, was behind by just 248 votes as of Friday morning, with as many as 10,000 ballots still to be counted, according to the Jefferson County Clerk and Record’s Office. “Don’t close up shop yet,” said Beth Clippinger, spokeswoman for the clerk and recorder’s office. Most of the outstanding ballots were cast on Election Day, which saw a “humongous” turnout, according to Clippinger.