Story highlights Democrats lead in Nevada early voting by 6 points -- and 13.7 points in the state's key county

The lead matches, and in some regions bests, President Obama's 2012 numbers

(CNN) Democrats have built what could be an insurmountable edge in Nevada at the end of early voting in the Western battleground state.

In key regions, the party is matching or outpacing the lead President Barack Obama had at this point in 2012 on his way to a nearly 7-percentage-point win of the state's six electoral votes.

Clark County -- home of Las Vegas and more than two-thirds of Nevada's active registered voters -- saw its record for single-day early vote turnout shattered Friday when 57,174 people cast their ballots, according to data from the Nevada secretary of state's office that's based on the party registration of those who have voted.

Overall, Democrats have built a lead of more than 72,000 votes there -- 13.7 points ahead of Republicans, and slightly larger than Obama's 2012 edge.

It's no surprise Democrats are ahead there, but the gap is more than double what Republicans say they need it to be. A GOP official said Trump could afford to lose Clark County by 6 points and still carry the state.

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