ST. PAUL — Representatives of Minnesota businesses large and small ramped up pressure on state lawmakers Thursday to collect sales taxes on purchases made through online-only retailers.

The public push included an all-hands-on-deck news conference outside a small St. Paul toy store. It comes with time winding down on the 2012 session. The plan has bipartisan backing and support from Gov. Mark Dayton’s administration, but advocates worry it is stalled.

State Revenue Commissioner Myron Frans said Minnesota could expect about $4 million next year and more later if purchases made through Amazon, Overstock.com and others had Minnesota tax applied.

The debate over whether online retailers must collect taxes from customers in other states centers around a decades-old U.S. Supreme Court decision involving a mail-order company. In that case, the court said retailers only have to collect state tax if they have a physical presence in a state, such as a retail store.

Amazon has argued for finding a federal solution rather than state-by-state laws on sales taxes on Internet purchases. But the company has reached deals with some states, including California.