Answer

Indiana does not currently have runoff elections.

Typically, in a runoff election, if no candidate receives a majority of the votes, another election between the top two contenders is held at a later date. The problem with this approach is that it is expensive, time consuming, and difficult to maintain voter interest in a runoff election weeks after the general election. So the winner of a runoff election might be elected with even fewer voters voting.

The recent runoff elections in Georgia for a US Senate seat is a good example of this phenomena. In November 3, 2020 election, 4,952,175 votes were cast in the Senate race with the following results:

Perdue 49.73% (2,462,617 votes)
Ossoff 47.95%. (2,374,519 votes)
Hazel 2.32%. (115,039 votes)

If RCV had been in place for this race, the second choice of Hazel supporters would have rolled over to either Perdue or Ossoff, and either Perdue or Ossoff likely would have crossed the 50% threshold. However, under Georgia law, a runoff election between Perdue and Ossoff was held on January 5, 2021, with the following results:

Perdue 49.39% (2,214,979 votes)
Ossoff 50.61%. (2,269,923 votes)

In the January runoff race, 4,484,902 voters voted, 467,273 fewer voters than in the general election in November. Moreover, Ossoff won the election in January with fewer votes than Perdue received in the November general election, arguably making Ossoff’s election less representative of the majority of people in Georgia than Perdue’s election would have been. This is an example of a race that might have had a different, potentially more representative, outcome with RCV. This was also the most expensive Senate race ever. For further information on this race, click here and here.