More than 30 million votes have been cast already across 38 states in early voting in the ongoing 2016 U.S. election with four days into the Nov. 8 elections.
Early voting data from several battleground states showed that Democrats are building an early voting lead in North Carolina and Nevada.
However, Republicans maintain an edge in Florida and Ohio as well as in Arizona, while Democrats are also ahead in Colorado and Iowa, according to a CNN/Catalyst polls.
Both Democratic nominee Hillary Clinton and Republican Donald Trump are encouraging their supporters to hit the polls early.
So far, about 7.4 million registered Democrats and about 6.4 million Republicans have done just that.
The polls also showed that not all Democrats are voting for Clinton, and not all Republicans support Trump.
In Arizona, a battleground state where about 1.3 million people have already voted, registered Republicans are ahead by about 71,000 votes or 5.5 per cent.
Last week, Republicans lead over Democrats was only about 11,500 while that lead is now more than 71,000.
In Colorado, a state where the election is almost entirely conducted by mail, Democrats have consistently led Republicans in terms of ballots returned.
There are some new polls out of Colorado that show a tightening race, with the Democratic lead one week ago was about 5.6 per cent.
In Florida, the largest electoral state with 53 Electoral College, Republicans have been steadily ahead in the early vote by about 0.5 per cent over the past week.
The Republicans lead is tiny with only about 16,000 votes out of more than 2.7 million cast but it is seen as a strong sign for Republicans which trailed Democrats by more than 73,000 votes in 2012.
Democrats hope to gain the big gains among Latino voters enough to overcome whatever drop-off there is in the African-American vote.
Democrats lead Republicans in Iowa, but they have been consistently behind their winning 2012 pace.
Right now, about 41,000 more Democrats than Republicans have voted in the State but at this point in 2012, they had an edge of more than 60,000 votes, according to the data.
However, a majority of voters in Iowa typically cast their ballots on Nov. 8.
In Nevada, the early vote in Nevada has tracked closely with 2012, a year when Democrats built a significant lead during the early voting window
Registered Democrats are ahead by about 29,000 votes right now over registered Republicans.
The polls showed a slight drop from the 31,000-vote lead they had in 2012 when Democrats were ahead by about 38,000 votes, or 7.6 per cent.
Democrats are padding their lead in North Carolina, consistently increasing their raw vote advantage over Republicans as more early voting locations open across the state.
Registered Democrats are ahead by about 243,000 votes across the state, whereas in 2012, the Democratic lead was more than 307,000 votes.
African-American turnout is lower this year and they have dropped as a share of the early electorate from 28 per cent in 2012 to about 23 per cent currently.
The overwhelming majority of African-Americans that voted already in North Carolina were also registered Democrats.
In Ohio, registered Republicans expanded their lead ahead of Democrats by almost 66,000 votes, or about five points.
Early voting is down across Ohio this year due likely to the cutbacks imposed by the Republican-controlled legislature in 2013, to the number of days of early voting.