Barack Obama was able to get Obamacare passed largely because he had a group of Democrats in Congress who were not running for re-election and thus had no fear of the voters. They overreached and the Democrats were swept out to the minority in the House of Representatives. In fact, the voters in 2010 wrecked devastating losses on the Democrats nationwide.
When politicians, regardless of party, are no longer accountable to the voters they tend to do extremely arrogant things, they tend to overreach badly, and they tend to collapse.
Barack Obama is, going into his second term, already one of the most arrogant politicians in America. Remember how his team told the public unconvincingly that Barack Obama was “among the most sophisticated consumers of intelligence on the planet’? Remember how Obama viewed himself all the way back in 2008?