Van Buren , initially the leading candidate , opposed immediate annexation because it might lead to a sectional crisis over the status of slavery in the West and lead to war with Mexico .
The annexation of Texas was the chief political issue of the day .
Van Buren , initially the leading candidate , opposed immediate annexation because Texas might lead to a sectional crisis over the status of slavery in the West and lead to war with Mexico .
The annexation of Texas was the chief political issue of the day .