Former prime minister Alexander Stubb and former foreign minister Pekka Haavisto go head-to-head in a run-off election for the presidency of Finland on Sunday after no candidate secured sufficient votes in the first round two weeks ago. Polling stations will be open from 9 am to 8 pm local time (0800-1900 GMT), with exit polls expected immediately after they close. A preliminary result is expected in the course of Sunday evening. Stubb, a conservative, and Haavisto of the Greens garnered the most votes of the nine candidates in the first round. Stubb got 27.2% of the vote, Haavisto 25.8%. They…