Prime Minister Boris Johnson vowed Wednesday to “fight for every vote” after polls predicted a close finish to Britain’s general election aimed at settling the Brexit crisis. The former London mayor and foreign minister has been hammering home his “Get Brexit Done” message, to win a majority which would enable him to get the deal approved. The YouGov study said the Tories were on course for a 28-seat majority in the 650-seat House of Commons under Britain’s first-past-the-post system.