Tim Kaine Eyes 'Checkmate States' in Today's Presidential Election

— -- After voting in his home state of Virginia, vice presidential hopeful Sen. Tim Kaine said today's election could come down to four "checkmate states," which he and running mate Hillary Clinton are keeping a close eye on.

"The ones we watch really close are checkmate states. Those are states where if we win, we know Hillary will be president. And I say this about North Carolina, Pennsylvania, Florida, Ohio," Kaine said today on "Good Morning America." "I think if we win any of those four, Hillary will be president."

He said he thinks she has a shot at winning all four "checkmate states" but the race could be tight in some of them.

Kaine and his wife, Anne Holton, were among the first people to vote at the Hermitage Methodist Home in his hometown of Richmond early this morning — the polling site he has used for more than 20 years. He will head to New York later today to join his running mate and their supporters for the vote count.

While speaking to reporters after voting, he admitted that the thought of millions of people nationwide voting for Clinton's Republican rival, Donald Trump, was "troubling." But he invoked Vice President Joe Biden's words at Monday night's rally in Philadelphia about exploring what "drove the other side."

"There are some aspects about it that are troubling, but what Joe said, I have heard Hillary say too. There are a number of people voting for Donald Trump because of the anxieties they have about the economy, and we have folks voting for us with similar anxieties about the economy," Kaine told reporters in Richmond.

During the interview on "GMA," he said the soaring turnout of early voters across the country has kept him optimistic.

"Democracy always works better the more people participate," Kaine said. "I just hope we see record turnout for what I believe is going to be a history-making election."

ABC News' Jessica Hopper contributed to this report.