US election: Obama and Romney target key swing states
The US presidential candidates have been addressing large crowds ahead of Tuesday's election.
With polls showing Barack Obama and Mitt Romney virtually neck-and-neck, the two men are focusing their efforts on voters in key swing states.
In Ohio, Mr Obama said real progress had been made over the past four years, but that he wanted to continue the fight to give everyone a "fair shot".
Mr Romney told a New Hampshire rally he would lead voters to a "better place".
Barack Obama was campaigning in Ohio, Wisconsin, Iowa and Virginia on Saturday, while Mitt Romney targeted New Hampshire, Iowa and Colorado.
Mr Romney told a crowd in Colorado: "I have got a plan. I can't wait to get going. He [Mr Obama] is hoping we will settle, but Americans don't settle, we build, we aspire, we listen to that voice inside that says: 'We can do better'."
In Virginia, the president was joined by former President Bill Clinton, who said Mr Obama had done "a good job with a bad hand" and deserved another term.
"He [Mr Obama] knows that an economy that builds the middle class and gives poorer people an honourable way to work their way into it is a lot better than four more years of trickle down," Mr Clinton told the rally.
Both candidates were visiting the Iowa town of Dubuque within hours of each other.
Mr Obama, addressing crowds of supporters in Mentor, Ohio, said the election was a choice between "two different visions for America: the top down vision that crashed the economy, or a future built on a strong and growing middle class".
Republican Mr Romney, opening his three-state campaign day in New Hampshire, told supporters to "vote for love of country".
"It is time we lead America to a better place."
Opinion polls suggest the rivals are almost tied, although Mr Obama is slightly ahead in most swing states.
The BBC's Bridget Kendall, reporting from Ohio, says it is hard to predict accurately who might win.
Mitt Romney does not seem to have the same confidence he had a week earlier ”
But, the Obama campaign has a new confidence in the past week, she says, which may be down to the positive response the president's handling of Sandy storm aftermath has received - a situation Mr Romney has found difficult to counter.Tipping point?
Correspondents say Mr Romney faces the tougher task on Tuesday, as he must win a majority of the nine most keenly contested states.
But Mr Obama's opinion poll lead in all the swing states is within the margin of error.
The election is run using an electoral college. Each state is given a number of votes based on its population. The candidate who wins 270 electoral college votes becomes president.
Ohio is proving to be a tough battle and, with 18 college votes, could prove a tipping point.
Barack Obama campaigned hard in the state on Friday, highlighting his decision to bail out indebted US car makers in 2009, a move that was politically unpopular but which he says helped restore the industry.
Also on Friday, Mr Romney staged his biggest rally of the campaign so far - 18,000 people - in West Chester, joined by former primary rivals Rick Santorum and Rick Perry, as well as the defeated 2008 presidential candidate John McCain.
US election - the essentials
Mr Romney has tried to make inroads into Pennsylvania, where opinion polls suggest the Democrats lead by four to five points but which would be a crucial boost to his chances if he could secure its 20 college votes.
The Republican challenger has also wooed Michigan and Minnesota, forcing the Democrats into late advertising there.
Early voting has been a key focus of this presidential election - some 25 million voters have already cast ballots in 34 states and the District of Columbia.
Some states have released the affiliation of early voters, giving Mr Obama an edge in Florida, Iowa, Nevada, North Carolina and Ohio, while Mr Romney is favoured in Colorado.
However, the figures suggest Mr Obama does not have the lead he had over John McCain four years ago.
Nevertheless, the Obama team has released data showing that two-thirds of those who have voted early are women, young people, blacks and Hispanics - demographics the Democrats say favour them.
The BBC will be providing full online live results of the US presidential election on 6 November. More details here