LANSING — Michigan would no longer automatically treat 17-year-old criminal defendants as adults under bills that cleared a significant legislative hurdle Wednesday and may soon reach the desk of Gov. Gretchen Whitmer.

The Republican-led Senate, for the first time, overwhelmingly passed “raise the age‘ measures after not embracing them in past sessions. The GOP-controlled House planned to approve a similar plan Thursday, after which lawmakers will work to resolve differences over how to ensure the state fully funds an additional $17 million to $47 million in annual juvenile justice costs for counties. The legislation would take effect in October 2021.

“I think it’s ironic that we want kids to be kids ... sometimes when they cross the line, they do something wrong, we immediately want to treat them as an adult,‘ said Rep. Daire Rendon, R-Lake City, a sponsor of the House version of the bill package.

Rendon noted that other states favor treating older teens as juveniles.

In 45 states, the maximum age of juvenile court jurisdiction is 17, while Missouri’s law increasing the age to 17 will take effect in 2021. Michigan, Texas, Georgia and Wisconsin draw the line at age 16, according to the National Conference of State Legislatures.

Prosecutors could still automatically try 14-, 15-, 16- and 17-year-olds as adults for certain violent offenses, such as murder and rape.

The bills won bipartisan approval, which Rendon described as one reason she thinks the bills have momentum.

“This is something that really speaks to bipartisanship,‘ Rendon said.

One Republican voted against one measure and another opposed the entire package.

Sen. Jim Runestad of White Lake Township expressed concern that many “very violent‘ repeat offenders would not be waived into the adult justice system at age 17 and would instead be detained with younger juveniles.

“I wanted more restrictions with the 17-year-olds before we’re just going to willy-nilly trust these prosecutors,‘ Runestad said.

Supporters of the legislation argue that 17-year-olds could receive age-appropriate rehabilitation services that are unavailable in the less lenient adult corrections system.

The goal is to rehabilitate young offenders “instead of throwing them into big-boys’ prison, if you will,‘ Rendon said.

The nonpartisan House Fiscal Agency projects Michigan had more than 7,200 17-year-old defendants in 2016. If they had been treated as juveniles, 763, or 11%, would likely have been moved to adult courts while 4,081, or 56%, would likely have been tried as juveniles. The remaining 33% had traffic violations.

A spokeswoman for the Democratic governor did not give her stance on the legislation, saying it is under review.

EDIT: This story has been updated to reflect that the story ran after a planned hearing on Thursday of last week.