Back in 2004 and 2005 I organized two separate marriage-as-God-defines-it rallies at the Rhode Isand state house. We had a lot of support from the evangelical community...about 400 people in attendance each time...but the Catholic churches didn’t lend their support at all. They didn’t want anything to do with it.
I believe you; however, you would find that traditional Catholics parishes -- Latin Mass and old-fashioned morals -- are 100% supportive of what you are doing.