So far in 2012, foes and backers of the measure that would constitutionally ban same-sex marriage have raised more than $7 million, according to campaign finance reports filed Tuesday and released Wednesday.

The overwhelming majority of these contributions — $5.96 million — have gone to Minnesotans United for All Families, the main organization opposing the amendment.

Minnesota for Marriage, the lead group supporting the amendment, has raised approximately $1.2 million in 2012.

Minnesota’s Roman Catholic Bishops recently sent letters to Catholic households asking them to “vote yes” on the amendment and to consider donating to Minnesota for Marriage.

On Tuesday, Minnesota for Marriage announced new billboards touting the words “Marriage = One Man + One Woman” and “Vote YES.”

Meanwhile, Minnesotans United aired its first TV ad last week that urges Minnesotans to vote “no.” It features lifelong Republicans and Catholics John and Kim Canny describing their evolving view of same-sex marriage.

They encourage Minnesotans to take a second look at the issue and to vote no on the amendment.

Multiple polls have found Minnesotans are deeply split on the amendment. Some show supporters with a slight edge, and some show opponents in the lead, but the divide often falls within the margin of error.