Representatives Rebecca Kubacki and Kathy Heuer lost their seats to primary challengers on Tuesday.
Whether to amendment Indiana's constitution to define marriage as between a man and a woman was the main issue debated in the 2014 session.
The National Organization for Marriage wants to put HJR-3 on the ballot despite lawmakers passing a measure indicating it must be approved in 2015 or 2016.
The amendment's passage is the first step to putting HJR-3 on the ballot in 2016.
The Senate today did not reinsert the second sentence to the proposed constitutional amendment defining marriage as between a man and a woman.
A group of young adults gathered at the statehouse today to show their support for the proposed amendment defining marriage as between a man and a woman.
House Joint Resolution 3 has been moved to a new committee after several members of the original committee said they were undecided on the issue.
Many gay rights supporters worry HJR-3 would do more than solidify a ban on gay marriage. They say it could disrupt existing same-sex benefits.
Indiana Newsdesk's Joe Hren speaks with Greencastle Mayor Sue Murray, in our weekly Ask The Mayor segment.
The Archdiocese of Indianapolis affirms the dignity of all humans, while defining marriage as between one man and one woman.