Kentucky's top election official says she expects 20 percent of the state's more than 3.2 million registered voters to cast ballots in Tuesday's primary elections.
Secretary of State Alison Lundergan Grimes said more than 12,000 people have already cast absentee ballots for a host of local, state and federal races. Of those, 7,533 were cast by registered Democrats and 4,821 were cast by registered Republicans.
The race most likely to drive turnout will be the Democratic presidential primary between former Secretary of State Hillary Clinton and Vermont Sen. Bernie Sanders.
Kentucky will not have a Republican presidential primary. The state party held a presidential caucus in March, which was won by Donald Trump.
Grimes said the lack of a Republican presidential race will likely drive down turnout on the Republican side.