* Quick exit means affair likely to blow over quickly
* Scandal threatened to hurt Merkel's popularity
By Annika Breidthardt
BERLIN, Feb 10 (Reuters) - German Education Minister Annette Schavan has done her friend Angela Merkel a good turn by quitting, sparing the chancellor months of distraction in an election year that has already got off to a bad start.
Having been stripped of her doctorate over allegations she copied parts of her thesis 33 years ago, Schavan stepped down on Saturday, saving Merkel the prospect of her friend's fate overshadowing more than seven months of election campaigning.
The scandal had already begun to hurt the popularity of Merkel, which has survived earlier high-profile resignations. A poll conducted on Thursday - two days before Schavan's exit - indicated 62 percent of Germans felt the affair was damaging Merkel and her party; among CDU supporters it was 68 percent.
Schavan said she would take legal action against the university that voided her title but did not want to do damage to her ministry.
"Whatever the outcome of such proceedings, (Merkel) would (have been) confronted with these allegations throughout the whole election campaign," political scientist Gero Neugebauer said before Schavan stepped down.
Merkel had already got off to a bad start to 2013. Her Christian Democrats (CDU) lost control of Lower Saxony in January despite fielding a popular candidate, who, like Merkel herself, was seen as his party's greatest electoral asset.
Opposition politicians say Lower Saxony marked a turning point in polls. Since then, the Social Democrats have climbed slightly towards 30 percent while the Christian Democrats are inching down towards 40 percent.
Merkel's problems also include poor poll results for her junior coalition partner, the Free Democrats, and a budget row in Stuttgart over a planned new train station.
Media poke fun at Merkel for the five cabinet reshuffles in her second four-year term, saying that expressing "full confidence" in a minister - a term used by Merkel's spokesman on Wednesday - usually meant he or she would step down within days.
But the dignity Merkel allowed Schavan in her exit is likely to have helped the chancellor herself.
Merkel faced the press together with her friend, unlike in previous resignations, and appeared unusually emotional, praising Schavan and not mentioning the plagiarism charges.
Even opposition politicians lauded Schavan's achievements as minister and there was widespread agreement that Schavan's move was "unfortunately right", according to one newspaper headline.
"Schavan is a highly decent and competent colleague whose fate I am exceptionally sorry about," SPD leader Sigmar Gabriel was quoted as saying.
On Sunday, Berlin's chattering class had already turned its attention to the next political scandal.
Prosecutors have opened preliminary proceedings against Gregor Gysi, a key figure in the Left Party's campaign, over allegations he lied about links to the former East German secret police, a claim he has fought repeatedly over two decades.
In the end, Merkel's biggest concern may be "plagiarism hunters" investigating her own thesis. The founder of internet platform "SchavanPlag" has said he has been offered money if he finds mistakes in Merkel's doctoral thesis.