Americans going out to polling sites Tuesday were reporting lengthy lines and hours-long wait times, especially in the toss-up states that will determine who becomes president.

Some polling sites in Philadelphia, Pennsylvania described turnout as "unprecedented," with voters waiting several hours to even enter the buildings, the Philadelphia Inquirer reported.

Questlove, best known for being the drummer and frontman of the band The Roots, said on Instagram he was expecting a two-hour wait in Philadelphia.

He posted an image of Netflix television titles and wrote: "Welp, Netflix about to be my friend in this two hour wait of a line ... Happy to see this positive turnout."

However, voters at other places in Philadelphia reported breezing through the process.

Hillary Clinton, the Democratic nominee, must hold onto the urban and college-educated voters of Philadelphia and Pittsburgh in order to win Pennsylvania, where Republican Donald Trump has had success with working-class voters.

In the swing-state of New Hampshire, Twitter users posted images of lines stretching far outside polling places in the state's biggest city, Manchester, even before they officially opened.

There were concerns ahead of Tuesday about voter intimidation tactics from supporters of Trump, who has repeatedly called the election "rigged" despite no evidence to support the claim.

Kristen Clark, the president of the Lawyers' Committee for Civil Rights Under Law, a group running an independent effort to address voter complaints, said it had received scattered reports of voter intimidation in parts of the battleground state of Florida.

But if there was trouble at the polls, the cause often was due to technical issues.

The worst appeared to be in Durham County, North Carolina, where officials decided to extend opening times there by one and a half hours after computer failures at six sites prevented workers from checking voter registration.

North Carolina has been one of the most highly contested states in this election. The state's many African American voters pushed it to the Democrats in 2008, but it returned to Republicans four years later.

Meanwhile, Trump tweeted, "Utah officials report voting machine problems across entire country," without giving further details. Some Twitter users commented that he probably meant "county," with no reports of a nationwide glitch.

In the western battleground state of Nevada, a judge denied a request by the Trump campaign to isolate ballots from four early voting sites.

Campaign lawyers had questioned the legality of the polling sites staying open two hours beyond their designated time on Friday, and asked that the ballots cast during that time be set aside in case of future legal action.

Most Americans cast their ballots on Tuesday, but Nevada is one of several states that also allows early voting.

Trump supporters speculated that the move to keep the polling places open was taken to boost Clinton's chances in Nevada. The four sites were in areas with a strong Hispanic population, a demographic that Trump has not proved popular with.

Judge Gloria Sturman told the Trump lawyers that their petition was without merit and could potentially violate the privacy of the poll workers.

Election officials said the poll times were not extended, but that people who were already in line at the time of the official close were allowed to vote.

"On Friday, most if not all of our early voting locations had lines of voters when their scheduled closing time passed," Clark County officials wrote in a statement following the judge's ruling.

"As has been our practice for many, many years those early voting locations continued processing voters until the lines were gone," it continued.

Had Trump's petition to the Clark County court been successful, it could have laid the groundwork for the votes being thrown out all together.

Democrats called the legal action an attempt to undermine the rights of voters.

"Enough with cowardly politicians protecting themselves by suppressing the vote," Bernie Sanders, the one-time presidential hopeful turned Clinton supporter, reacted on Twitter.