Minnesota Gov. Mark Dayton, right, is likely to sign an online voter registration bill when it reaches his desk. (Jim Mone/AP)

Minnesota must put an immediate freeze on its new online voter registration system after a judge ruled Monday the Secretary of State overstepped his authority in creating the new system.

Ramsey County District Judge John Guthmann said Monday that Secretary of State Mark Ritchie (D) didn’t have the authority to set up the system. A bill to allow online registration got bottled up in the legislature last year, and both Democrats and Republicans complained when Ritchie moved to unilaterally create the system.

The state House passed a bill this month  that authorized an online registration system similar to Ritchie’s. The state Senate, which is controlled by Democrats, is set to vote on the bill Tuesday. In the House, even Republicans who brought the lawsuit against Ritchie voted for the measure.

“We don’t have concern about the policy, frankly. Other states have implemented it. We are interested in finding ways for people to register in a convenient manner,” state Senate Republican leader David Hann said in an interview last year.

Gov. Mark Dayton (D) is likely to sign the bill once it passes.

Guthmann ordered Ritchie to shut down the system by Tuesday at midnight. About 3,600 voters have taken advantage of online registration since Ritchie opened the system last October, and Guthmann will allow those registrations to stand.

Minnesota has passed several election law changes over the past year, all of them on bipartisan votes. Dayton said last year he would veto any legislation that passed on party-line votes, even though Democrats control the legislature.

Eighteen states — not counting Minnesota — allow online voter registration, and four other states are in the process of implementing online systems. Online registration platforms only allow those with state-issued identification cards to sign up to vote. The states that allow online sign-ups include both deep red states like Kansas and Georgia, and deep blue states like California, Colorado and Washington.

Studies have found online registration can save states big money. Processing a paper registration can cost a state 83 cents, but it costs just 3 cents to process an online registration.