Polls opened at 6 a.m. In Lawrenceburg,a poll worker opened doors with a "here ye, here ye."
The Hoosier State is the only state in the country with a primary election Tuesday.
In Dearborn County, interest in the election is expected to be high with record turnout.
“It’s going to be big,” said Dearborn County Clerk Rick Probst.
In Lawrenceburg, interest in the polling day was growing Monday night as several colorful political signs started popping up around the polling locations.
"I've always voted since I was 18 years old,” said Ivan Watkins of Lawrenceburg. "It's our duty. We're Americans. We're supposed to vote.”
The primary on Tuesday in Indiana is considered a must-win for some presidential candidates.
"This is a big one. It's probably the most significant day in this primary cycle to this point,” said NKU political science professor Dr. Ryan Salzman.
Salzman says a lot of that has to do with timing, the number of delegates at stake and the ability for candidates to continue, or regain, momentum to clear a path to a presidential nomination.
There are 83 democratic delegates and 57 republican delegates up for grabs in Indiana on Tuesday.
"I think you would have already seen large numbers for the Indiana primary. Now, with this circumstance, it'll make them even higher, more than likely,” Salzman told FOX19 NOW.
That’s what election officials in Dearborn County expect on Tuesday. Probst says early voting numbers this year exceed those in 2012 by nearly 400 ballots. He also told FOX19 NOW that he’s expected upwards of 15,000 voters in Dearborn County on Tuesday compared to 6,800 in 2012.
"We need to go and make the choices and not just let people make decisions for us. To me, I want to be one of the people that make the decisions,” Watkins told FOX19 NOW.
Polls are open until 6 p.m.
FOX19 NOW will have all the results as they come in.