Answer:
One problem with having the runner-up be vice president, is differing opinions.
Explanation:
For example, if the President was associated with the Federalist party, and the vice president/runner-up was associated with a party opposing the Federalist party, they might have a hard time agreeing on matters. Or this could cause disputes among the President and Vice President, which could affect how they run the country.
What do you mean the government was never replaced.