Union leaders in recent days have urged Senate Minority Leader Chuck Schumer, D-N.Y., and the Democratic Senatorial Campaign Committee to end their support for Gov. Janet Mills in Maine’s Senate primary, pointing to what they see as her weaker record with labor. United Auto Workers President Shawn Fain had a conversation with Schumer this month to discuss the race, among other topics, two people familiar with the call told NBC News. The UAW is supporting Mills’ opponent, Democrat Graham Platner, while Schumer and the DSCC are supporting Mills. A person familiar with the call said Fain discussed with Schumer what he views as the “shortcomings” in Democratic leaders’ approach to the 2026 midterms, “particularly their failure to adequately listen to working-class voters.” Fain cited the Maine contest as an example, this person said.…