Republican presidential candidate Ohio Gov. John Kasich addresses supporters during a campaign stop at Michigan State University, Feb. 15, 2016, in East Lansing, Mich.
Photo by Carlos Osorio/AP

Early voting underway in upcoming primary states

While all of the attention this presidential primary has been focused on the early primary states of Iowa, New Hampshire, South Carolina and Nevada, it’s worth noting that thousands of voters have already cast their ballot in upcoming nominating contests.

Of the 19 non-caucus states voting between March 1, the first Super Tuesday, and March 15, the second so-called Super Tuesday, early voting is currently taking place in 11 of the states.

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Delegate-rich Ohio is one of them. While its primary is March 15, voters have been able to vote since last Wednesday, four days before South Carolina Republicans and one week after its governor, John Kasich, captured second place in New Hampshire.

Matt Borges, head of the Ohio Republican Party, said he predicts one-third of voters will vote early in Ohio.

Voters are heading to the polls even as the field continues to narrow.

In Ohio, for instance, any candidate that dropped out after February 4 - Jeb Bush, Carly Fiorina, Mike Huckabee and Rick Santorum - will still be on the ballot but their votes won’t be tabulated.

Illinois, which also holds its primary March 15, began accepting votes in early February.

The only campaign that so far is organized to highlight early voting in upcoming states is Hillary Clinton’s. She held a get-out-the-vote event in Chicago last week and her husband Bill Clinton held one in Ohio the week before that.

Kasich, however, could greatly benefit from early voting in Ohio by just staying in the race during the period of early voting. He’s a popular governor there - boasting a 62 percent approval last fall - and he has the backing of the Ohio Republican Party, which is notifying its voters of who they are supporting - namely Kasich.

Because it’s a winner-take-all primary, winning its 66 delegates could be a significant boost to the governor who is embarking on a northern and Midwestern blue-state strategy to win the nomination.

This article originally appeared on NBCNews.com.

Illinois and Ohio

Early voting underway in upcoming primary states