(CNSNews.com) — Only 20 percent of Democrats say that President Barack Obama has been a better president than Bill Clinton, says the Gallup poll, while 56 percent of Americans told Gallup they believe Obama has been the same or worse than George W. Bush.

Among Independents, 67 percent say Obama is the same or worse than Bush.

Bill Clinton was one of only two presidents in history impeached by the House of Representatives. Near the end of his term, in the week before the November 2008 election, George W. Bush had 25 percent approval in the Gallup poll.

Thirty-five percent, overall, said Obama was about the same as Clinton and 50 percent said he was worse. Only 12 percent of the Americans polled by Gallup said Obama was a better president than Clinton.

Among Democrats, moreover, only 20 percent said Obama was a better than Clinton — while 51 percent said he was about the same and 29 percent said he was worse.