If you have a popup and don't need a weight distributing hitch, you can try one of these:
Towing Rack Hitch Bike Racks | etrailer.com
I had a Reese (similar to the Swagman S64675) with my 1988 Coleman Sequoia that I used for 6 or 7 years, with two adult bikes and 2 teenager bikes on it. Worked great. Pulled it with two different Grand Caravans.
It also allows you to take the bikes on the car to somewhere else besides the campground. You can't do that with the bumper or A-frame mounts.
They also make racks for the tops of popups, but 1) you need a good roof, and 2) A/C units get in the way. See this one:
On the plus side, they put most of the weight on the camper rather than the tongue.
1988 Coleman Sequoia - popup (1987-2007)
2012 Roo19 - hybid (2012-2015)
2016 Mini Lite 2503S - tt (2015 - ???)
2011 Traverse LT, 3.6L, FWD
2009 Silverado Ext Cab, 5.3L, 4x4, 3.73
2016 Silverado 2500HD Dbl Cab, 6.0L 4x4, 4.10