I am making a change to my 55 gallon tank. I had a few longear in the tank along with a red ear hybrid but they got too large and I let it get over grown with algae. Interesting colors and interactions but I am looking to reset it to smaller fish. The one fish I have always had problems with (when I was younger) was the darters. I don't remember getting them to survive for a long period. My 55 gallon is in my home office with no heater and the maximum temperature it got last summer was about 76 degrees F. It kept pretty much in that range all year.

If I acclimatize them to this temperature will they survive long term at this temperature?

Usil

With enough surface agitation you should be ok, but watch out for power outages/clogged canister filters/etc.... I've lost a few that way. I think the depth of the standard 55 gallon doesn't give you much margin for error. I've noticed that the survivors generally are gasping for air on a leaf or filter pipe up high, so it's probably a good idea to deliberately provide elevated perches.

Run some powerheads with venturi air tubes and they'll be just fine.