Opponents of a proposed constitutional amendment which would define marriage as a heterosexual union are planning a rally in early January.

The Rally Against HJR-6 will be held at Monument Circle in downtown Indianapolis on Monday, January 6 to coincide with the start of the Indiana General Assembly's legislative session.

“As our legislators prepare to reconvene for the upcoming session, it is crucial that we continue to show them our opposition to HJR-6,” the group Freedom Indiana said in announcing plans for the evening rally. “We know that this anti-freedom amendment will hurt Hoosier families, our economy, and job growth. It's up to us to let our legislators know that HJR-6 goes against our values of Hoosier Hospitality.”

The Republican-controlled House and Senate approved HJR-6 in 2011. A needed second vote before heading to voters in November is expected to take place early in the upcoming session.

The political climate surrounding the issue of gay nuptials has shifted dramatically in the intervening years since the amendment received its initial approval. After the U.S. Supreme Court knocked down a key provision of the Defense of Marriage Act (DOMA) in June, challenges to numerous state bans were filed in federal courts throughout the country. Victory for marriage equality activists in Utah last week could signal the beginning of the end for such marriage amendments.

(Related: Stay in Utah gay marriage ruling could happen Monday.)