Today Russia is lucky if they have a hundred total modern fighters available, across the entirety of their military, to put into action that can fight with the F35. In the event of a NATO war, they can't dedicate that to one location, given the vast size of their territory to protect. They might be able to throw a dozen modern fighter jets at Denmark. So they'll have to simultaneously fight two dozen domestic European forces, and the US Air Force. Yeah, it'll turn out real well for them.
The UK had 113 Typhoons in 2013 and Germany had 112. When they're all delivered, the UK will have 160 and Germany 140. France has 95 Rafales and will eventually have 180. Sweden is not NATO, but has around 130 Gripens. Norway and Denmark have around 90 F16s between them, though you probably wouldn't call them modern. Not sure what the US has deployed in Europe.
Edit: not really modern, but Belgium, the Netherlands and Poland have another 150 F16s between them. Poland also has 30 or so MIG 29s.
