Yes, it shouldn't make much difference at all.
You can see using VK1OD's transmission line calculator: http://vk1od.net/calc/tl/tllc.php
We can put a 50 ohm load on one end and see how the impedance changes
at the other end. On 40m, the impedance is about 50.5+j5 ohms, for an SWR
of 1.1 : 1. That won't make enough difference to worry about.
You can use this same approach to see the effect of different lengths of RG-6.