Democratic Attorney General Roy Cooper has a lead of roughly 5,000 votes in his attempt to unseat incumbent Republican Gov. Pat McCrory, and Cooper was quick to claim victory Tuesday night, telling supporters, “We have won this race.”

Not so fast, the governor’s team responded. “Currently, there are tens of thousands of outstanding absentee, military, and provisional ballots across the state” not yet counted, said campaign spokesman Chris LaCivita. The governor also insisted that until every vote had been counted and certified, the election was not over.

The governor is correct — election results won’t be certified until Nov. 29 — but if history is a guide, the GOP incumbent has an uphill battle to secure a second term. More than 110,000 absentee and provisional ballots remain uncounted or unaccounted for, but we have no way of knowing how many of them are valid, and how many legitimate ballots will support McCrory, Cooper, Libertarian Lon Cecil, or a write-in candidate.

Why are so many votes still out there? The State Board of Elections reports that nearly 3.2 million North Carolinians “requested” absentee ballots; this includes the 2.95 million people who took advantage of early voting, which is counted as “one-stop” absentee balloting.

Of the remaining 237,205 absentee ballots, 67,601 had not been returned by election day. These ballots could have been requested by military personnel, North Carolina residents living overseas, or any other registered voter who preferred not to cast a ballot on election day. The ballots must have been postmarked no later than Nov. 8, and need to reach the board of elections by Nov. 14 (for civilian ballots) or Nov. 17 (military ballots) to be counted.

Some, perhaps many, of these ballots will get in on time and — if valid — count. For the governor to win, he’d better hope for a big late turnout, and one that’s skewed in his favor.

Of the 175,000 mail ballots counted so far by the Board of Elections, McCrory got nearly 91,000 (52 percent), Cooper 82,000 (46 percent), and Cecil 3,500 (2 percent).

If every outstanding mail ballot were returned, and the previous percentages held, McCrory would get about 4,050 more votes than Cooper — not enough to close the deficit.

Then there are the more than 44,000 “provisional” ballots that were cast on Election Day. These came from voters who didn’t have registrations on file at their precinct, or had moved without notifying the elections board of their current address, or had some other problem verifying that they were eligible to vote. The News & Observer reported that about half the provisional ballots cast in 2012 were ruled ineligible, though if that percentage holds this year, it’s more than enough potentially to reverse the outcome of a very close race.

Except provisional ballots tend to favor Democratic candidates. During the 2012 race for governor, of the 22,000 provisional ballots counted, then-Lt. Gov. Walter Dalton got 1,700 more votes than McCrory.

And in 2004, when Republican Bill Fletcher led the Election Day returns by 3,500 votes in his contest against Democrat June Atkinson for state school superintendent, provisional ballots swung heavily Democratic, and Atkinson got a narrow win. (Fletcher unsuccessfully challenged the outcome in court, and Atkinson wasn’t sworn in until August 2005.)

To be sure, even if Cooper is declared the winner Nov. 29, McCrory can demand a recount if Cooper’s margin of victory is less than 10,000 votes. Perhaps there might be enough errors or spoiled ballots to change the outcome.

But those are tall odds, once again demonstrating that in our tightly contested state, your vote really can make a difference.