The Republicans will be in a position of campaigning on the truth but they will be faced with a hostile media. I don't think they are in any danger of losing control of the House but the question is whether they can nationalize the election to the extent that they can take the Senate, a more difficult task than nationalizing the election to take the House.
When Axelrod says the Republicans are structurally in good shape I think he is referring to the safe Republican seats for the House members and the number of seats which Democrats must defend in the Senate.
When he speaks of the 2016 presidential election and implies that the Republicans will not win unless they go Rino, I don't think it matters so much what the ideology of the Republican champion is, what matters is his charisma.
The Democrats are not disadvantaged by campaigning on a lie, they have been doing that for a very long time