BERLIN (Reuters) - Voters in Saxony-Anhalt go to the polls on Sunday in the last test of German public opinion before September’s national election, one which could deal a blow to conservative Armin Laschet’s hopes of succeeding Chancellor Angela Merkel. Surveys in the state show a small lead for the Christian Democrats (CDU) of Laschet and Merkel, but the far-right Alternative for Germany (AfD) was running just 1 percentage point behind in the final poll published on Friday. Though most polls give the CDU a more comfortable lead, an AfD victory could deal a potentially crippling blow to the centrist Laschet"s electoral hopes, emboldening those on his party"s right who want a decisive break from the Merkel years. Merkel, in power since 2005, is stepping down after the federal election, and senior CDU officials concede that it will be tough to retain their party"s appeal to voters after 16 years in charge. National polls show the surging Greens almost tied with the CDU, with both holding around a quarter of the vote, lending the poll in Saxony-Anhalt, a sparsely populated state of just 2.2 million, an outsized significance. The AfD typically performs better in the former communist east, where the economy is weaker than in the west. Its strength in Saxony-Anhalt has already focused debate on the CDU"s relations with the political right. (Reporting by Thomas Escritt; editing by David Evans)