A proposal for major upgrades to the Xcel Energy Center complex in downtown St. Paul has a steep price tag at nearly $770 million, and supporters of the project hope the Legislature will pick up half the tab.

St. Paul has put a hefty price tag on its long-awaited plan to reinvent a crucial swath of downtown, including the Minnesota Wild’s Xcel Energy Center. For $769 million, the city would overhaul the NHL arena as well as the neighboring Roy Wilkins Auditorium and St.