Exit polls - US vs. Germany

Exit polls are conducted by a joint operation of many media organizations and the campaigns. 

Late in the afternoon on election day 2004 the results were clear: John Kerry was winning in Florida and enough key battleground states. Campaign manager Bob Shrum greeted Senator Kerry with, "Congratulations Mr. President-elect."

Ooops.

It turned out the exit polls were wrong. While 2004 was close, George Bush secured the popular vote AND the electoral vote. (2004 is the only year Republicans have won the popular vote since 1988. Our messed up Electoral College system is a story for a different post.)

Bottom line: Exit polls, when tallied and adjusted for demographic data, are very accurate but that analysis takes days to process. Nobody in American media is calling an election on the afternoon of election day.

******

Germany held an election in the state of Bradenberg yesterday. Immediately after the polls closed the media announced the ruling party edged the far right party. It was stated with confidence. The numbers initially reported:

SDP: 31%

AfD: 30%

(To confused Americans, in a parliamentary system, winning with 1/3 of the votes is common.) 

There was no doubt to the result. No waiting until all the votes had been counted. Today I read the final tally:

SDP: 30.9%

AfD: 29.2%

So, it ended up being almost a 2 point win. 

My question: How/why was the media so confident after polls closed when the exit polls were so close?