With three days to go until Election Day, a new Reuters/Ipsos poll released today shows President Barack Obama maintaining his advantage over Mitt Romney when it comes to the electoral college map.

Nationally, the poll shows the race virtually deadlocked, with Obama holding a slight lead over Romney among likely voters, 48% to 47%.

But results from Ipsos' tracking in the swing states shows Obama with an edge in several crucial battlegrounds — including Ohio, whose 18 electoral college votes are considered critical to either candidates' path to 270 electoral votes.

According to the survey, Obama leads Romney among Ohio's likely voters, 48% to 46%. Obama also holds a slim lead — 47% to 46% — in Virginia, another key swing state. The poll found the race tied in Colorado and Florida at 48% and 46%, respectively.

Romney has long been at a disadvantage in the electoral college. It is hard to imagine a path to victory for the Republican candidate that does not include winning Ohio. And while the race remains close — both nationally and in the swing states — a victory in the Buckeye State is looking increasingly less likely for Romney.

"It's really a game of inches. It's extremely close, but things look pretty optimistic for Obama, I would say, if you do the electoral math," Ipsos pollster Julia Clark told Reuters Sunday.