The Los Angeles Chargers have a few undrafted free agents who could make the final roster .  No wonder. Those Chargers signed 18 college free agents after the draft. One got a big payday because he plays a spot the team didn’t draft, but needs. Another got a massive contract because the Chargers liked him so much.  Under Jim Harbaugh and Joe Hortiz, undrafted free agents have a strong track record of being able to make the final 53, too. Just ask guys like Marlowe Wax, Nikko Reed and Eric Rogers from last year alone.  Perhaps the next man up? Try Western Michigan edge rusher Nadame Tucker, who arrives in Los Angeles after the Chargers leaned on an overlooked connection to make it happen.  NFL Undrafted Free Agency Steal? Chargers Might Have a Big One Nadame Tucker | Kirby Lee-Imagn Images The overlooked connection is a national thing, at least.…