The GOP can successfully nationalize the election and win the House and Senate again by:
1) Emphasizing the cut and run cowardness of the left
2) The situation in Israel who after years of restraint, appeasing (in some cases) and going along with a UN/Euro perspective are now at war with people who are butchers.
3) The lack of terror attacks on the US when there have been attacks around the world. Why is that?
4) We have 4.6 % unemployment. What's the problem folks.
5) Do we really want to unify with Mexico because the democrats are basically saying, you don't need papers to vote.
#6 the recent Senate vote on funding a wall on the Mexican border.
Zero dims voted for it.
Tax cuts vs. tax increases
Also:
Conyers wants to impeach the President. He would be chairman of House Judiciary.
Wrangel wants Reparations for slavery paid to Blacks of today, and tax increases out the wazoo. He would chair House Appropriations.
There's more, but you get the idea.
You could summarize this stuff in the form of "extreme Liberal mindset and record of those who would come to power in the House if Dems were to win." You could do the same for Reid and Leahy and Kennedy (you're talking about the Supreme Court here) etc. in the Senate.