Liberal Democrats were often befuddled by President Reagan’s “Teflon presidency.”

By their lights, Reagan could commit the most heinous acts, but their criticisms were usually shrugged off by the American people, who judged him a “nice guy” who deserved the benefit of the doubt. President Obama has enjoyed something similar during his first 2 1/2 years in office. Even as public opposition mounted to his policies — Obamacare, the failed economic stimulus program, cap and trade, skyrocketing government deficits — Obama retained a reserve of public good will reflected in consistently strong personal favorability ratings. People who didn’t like his policies generally still saw Obama as a likeable guy, somebody they would enjoy having over for dinner with the family.

But that may be changing.