US Elections

It meanders through two of the most hotly contested battleground states, both prime targets for Donald Trump and Hillary Clinton.

Ohio, the classic bellwether, has picked the winner in every presidential election since 1960. Pennsylvania has voted Democrat in the past six contests, but Donald Trump has designs on turning this reliably blue state Republican red.

Speaking on the campaign trail in Iowa, he outlined what he called an "entry-exit" programme, which would track those who overstay their visas.

He also reiterated his support for building a wall along the southern border with Mexico.

And he said he would stop illegal immigrants getting welfare benefits.

"I am going to build a great border wall, institute nationwide e-verify, stop illegal immigrants from accessing welfare and entitlements, and develop an exit-entry tracking system to ensure those who overstay their visas are quickly removed," Mr Trump said.

Speaking at a Mississippi rally, he said his opponent "sees people of colour only as votes not as human beings worthy of a better future".

Mr Trump added that Mrs Clinton and the Democratic party had taken advantage of the African-American community.

Mrs Clinton fired back, saying "he is taking a hate movement mainstream".

The Democratic presidential nominee called out Mr Trump for questioning the citizenship of President Barack Obama and for failing to disavow former Ku Klux Klan leader David Duke, adding that he was "peddling bigotry and prejudice and paranoia".

His campaign manager Kellyanne Conway said the mass deportation plan, which was a central plank of his campaign, was yet "to be determined".

Her comments at the weekend came after Mr Trump met with a new panel of Hispanic advisers.

He told Fox News on Monday he was not "flip-flopping" but wanted a fair plan.

"We want to come up with a fair but firm process. Fair but firm," he said, without giving specifics.

Trump, reading from prepared remarks on Thursday night, acknowledged that he sometimes says "the wrong thing" in an astonishing act of contrition that signaled Trump's willingness to break from his characteristic brashness and bare-knuckles style that carried him to victory in the Republican primaries, but risks dooming him in the general election.

Mrs Clinton broke the news in a tweet late on Friday. She plans a formal announcement on Saturday.

Mrs Clinton passed over more left-leaning candidates in favour of the 58-year-old senator, who is a strong supporter of free-trade agreements.

His home state of Virginia is a major battleground in the coming election.

Who is Tim Kaine?

Mr Kaine speaks fluent Spanish and could help the Clinton campaign maintain its support among Hispanic Americans - a growing voting bloc.

"The crime and violence that today afflicts our nation will soon come to an end," he said in Cleveland.

Painting a bleak picture of the state of the country, he said his presidency would usher in a new era putting America and ordinary people first.

His speech comes a day after Senator Ted Cruz failed to back him.

The senator, who was his bitter rival during the primary contests, was booed off the stage by Mr Trump's supporters.

Mr Trump's campaign planned to announce his selection on Friday, but cancelled the event because of the attack in Nice, France.

Sources close to campaign told ABC News that Mr Pence accepted the offer.

However, Mr Trump told Fox News on Thursday evening: "I haven't made my final, final decision."

Mr Trump hopes Mr Pence can help him appeal to the party's conservatives.

Other candidates reportedly in the running were former House Speaker Newt Gingrich and New Jersey Governor Chris Christie.

Mrs Clinton's double-digit lead, which she has held over the past several months, has vanished - and with it, apparently, Democrats' dreams of a transformational 2016 victory that would leave Republicans wandering the wilderness for a generation.

What happened? A closer look at those poll numbers offers some clarity.

Police in riot gear fired smoke grenades into the crowd. Protesters also interrupted Mr Trump's speech at the rally in Albuquerque.

Mr Trump, the presumptive Republican presidential nominee, wants a wall to be built along the border with Mexico.

New Mexico is the most Hispanic state in the US.

'Still in diapers'

The protesters had gathered outside the Albuquerque Convention Center, with banners that read "Trump is Fascist" and "We've heard enough".