The Senate voted 25-10 for a bill to allow students, faculty and others to tote guns on college campuses.
Sponsor Sen. Curt McKenzie said Tuesday it's wrong to strip students and faculty of their Second Amendment rights.
The House will now consider the measure, where it's likely to pass.
Sen. Michelle Stennett opposed the bill, arguing it will burden schools with additional security costs and could escalate arguments.
A similar bill failed in 2011 in the Senate.
In debate Tuesday, McKenzie said he's addressed concerns about lack of training and the mixing of guns with alcohol that sank that version.
Retired law enforcement officers and those with Idaho's so-called "enhanced concealed carry permit" that requires training could pack weapons.
Heads of Idaho's eight public universities and colleges opposed the bill.