In 2010, Republicans took the House of Representatives by gaining 63 seats. They also picked up six U.S. senators and 675 state legislators, giving them control of more legislative chambers than any time since 1928. The GOP also won 25 of 40 gubernatorial races in 2009 and 2010.

These epic gains happened primarily because independents voted Republican. In 2010, 56% of independents voted for GOP congressional candidates, up from 43% in 2008 and 39% in 2006.

Today, independents look more like Republicans than Democrats, especially when it comes to health care. In a new Crossroads GPS health-care policy survey conducted in 10 states likely to have competitive Senate races and in House districts that lean Republican or are swing seats, 60% of independents oppose President Obama's Affordable Care Act. If this holds through 2014, then Republicans should receive another big boost in the midterms.

There is, however, one issue on which independents disagree with Republicans: using the threat of a government shutdown to defund ObamaCare. By 58% to 30% in the GPS poll, they oppose defunding ObamaCare if that risks even a temporary shutdown.

This may be because it is (understandably) hard to see the endgame of the defund strategy. House Republicans could pass a bill that funds the government while killing all ObamaCare spending. But the Democratic Senate could just amend the measure to restore funding and send it back to the House. What then? Even the defund strategy's authors say they don't want a government shutdown. But their approach means we'll get one.