$51-\left ( {10+13+8} \right )$
$=51-31$
$=20\left ( {票} \right )$
$13-8=5\left ( {票} \right )$
$\left ( {20+5} \right )\div 2$
$=25\div 2$
$=12\left ( {票} \right )····1\left ( {票} \right )$
$12+1=13\left ( {票} \right )$
答：后面的计票中小明至少还要$13$票才能当选.
$51-\left ( {10+13+8} \right )$
$=51-31$
$=20\left ( {票} \right )$
$13-8=5\left ( {票} \right )$
$\left ( {20+5} \right )\div 2$
$=25\div 2$
$=12\left ( {票} \right )····1\left ( {票} \right )$
$12+1=13\left ( {票} \right )$
答：后面的计票中小明至少还要$13$票才能当选.
