It wasn't a strategy to regain power, it was a mission to prevent the President from inflicting further harm upon the country (according to conservative thought). There were plenty of Republicans who thought it would cost them in the elections. But they saw it as worthwhile to prevent the expansion of the welfare state and the enshrinement of Obama's progressive agenda in law.

The notion that they wanted to make government work worse in order to bolster their claim that government doesn't work is what progressives tell each other, not what motivates conservatives. Ditto working class voters "voting against their interests", etc.