The table shows the results of a poll. A total of 450 voters selected at random were asked which candidate they would vote for in the upcoming election. In the poll, Candidate R received 250 votes and Candidate S received 200 votes.

According to the poll, Candidate R is expected to win the election. Assuming the total number of voters polled remains 450, what is the minimum number of additional votes Candidate S would need to receive in the poll to be expected to win the election?