It's not a bad idea: Pelosi's favorable rating runs about 20 percentage points behind her unfavorable rating. But will the strategy work?

It's possible, but midterm elections over the last 25 years suggest that Republicans are facing an uphill battle.

Consider the final pre-election polling in each midterm since 1994. When you look at the net favorability rating (favorable rating minus unfavorable rating) of the House leader of the party in opposition to the president, there's been basically no correlation with how the House midterms turned out. When you look at the difference in the net favorability of the House leader of the party in control of the White House and the net favorability of the House leader of the opposition party, there's been basically no correlation with how the House midterms turned out.

This is despite the party in charge of the White House running against a number of unpopular House leaders of the opposition in previous elections. Democrats tried to run against Newt Gingrich in 1994 and 1998 . They did the same in 2010 and 2014 against John Boehner. Their record is at best mixed, as the president's popularity has been the most important factor.

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