BERLIN (Reuters) - German Chancellor Angela Merkel s Christian Democrats (CDU) and the rival Social Democrats (SPD) are neck-and-neck ahead of a crucial regional election in the state of Lower Saxony, an infratest dimap poll showed on Thursday. The Oct. 15 snap election is being followed unusually closely because it follows just three weeks after national elections and will delay federal coalition negotiations, since parties are reluctant to alienate core voters by making compromises ahead of a key regional vote. The poll placed the CDU on 35 percent, just ahead of the SPD on 34 percent. The Greens were in third place on 9 percent, followed by the pro-business Free Democrats on 8 percent. The radical Left party was on 5 percent and the far-right Alternative for Germany (AfD) party was on 6 percent. 