This article is from the source 'bbc' and was first published or seen on . It last changed over 40 days ago and won't be checked again for changes.

You can find the current article at its original source at http://www.bbc.co.uk/news/election-us-2016-35457094

The article has changed 17 times. There is an RSS feed of changes available.

Version 3 Version 4
US elections 2016: Candidates in final pitch before Iowa vote US elections 2016: Candidates in final pitch before Iowa vote
(35 minutes later)
US presidential hopefuls are to make final pitches to people in Iowa, where the first votes for party nominations will take place later on Monday.US presidential hopefuls are to make final pitches to people in Iowa, where the first votes for party nominations will take place later on Monday.
Polls suggest that Republican Donald Trump has a narrow lead over Ted Cruz but both are well ahead of the others.Polls suggest that Republican Donald Trump has a narrow lead over Ted Cruz but both are well ahead of the others.
But the Democratic race is slightly tighter, with former US Secretary of State Hillary Clinton edging ahead of Vermont Senator Bernie Sanders.But the Democratic race is slightly tighter, with former US Secretary of State Hillary Clinton edging ahead of Vermont Senator Bernie Sanders.
Each party's nominee will contest the presidential election in November.Each party's nominee will contest the presidential election in November.
Over the weekend, the candidates barnstormed the sparsely populated Midwestern state of Iowa in an attempt to court undecided voters.Over the weekend, the candidates barnstormed the sparsely populated Midwestern state of Iowa in an attempt to court undecided voters.
Campaigning is expected to continue until voting starts at 19:00 local time on Monday (01:00 GMT on Tuesday).Campaigning is expected to continue until voting starts at 19:00 local time on Monday (01:00 GMT on Tuesday).
Candidates are hoping to triumph in this first electoral test because victory can spark campaign momentum as voting moves to the other states. While final rallies were held Sunday candidates have smaller meetings and parties planned as they try to gain last-minute votes.
This first electoral test is seen as key because victory can spark campaign momentum as voting moves to the other states.
Analysis - Jon Sopel, BBC North America editor, IowaAnalysis - Jon Sopel, BBC North America editor, Iowa
On the Democratic side, Hillary Clinton is facing a fierce challenge from the new kid on the block, Bernie Sanders, the 74-year-old senator from Vermont.On the Democratic side, Hillary Clinton is facing a fierce challenge from the new kid on the block, Bernie Sanders, the 74-year-old senator from Vermont.
He describes himself as a democratic socialist, he wants to raise taxes, he doesn't argue with the description of himself as a grumpy old man - but he has been attracting thousands and thousands of people to his rallies, and millions and millions of dollars in donations.He describes himself as a democratic socialist, he wants to raise taxes, he doesn't argue with the description of himself as a grumpy old man - but he has been attracting thousands and thousands of people to his rallies, and millions and millions of dollars in donations.
His popularity seems to fly in the face of all conventional political wisdom. But then again, everything about this race so far has flown in the face of all the hoary old truths.His popularity seems to fly in the face of all conventional political wisdom. But then again, everything about this race so far has flown in the face of all the hoary old truths.
All eyes on Iowa in unpredictable raceAll eyes on Iowa in unpredictable race
Among the wide Republican field, recent polling suggests that businessman Mr Trump has a comfortable, though not certain, lead over his main rival, Texas Senator Mr Cruz.Among the wide Republican field, recent polling suggests that businessman Mr Trump has a comfortable, though not certain, lead over his main rival, Texas Senator Mr Cruz.
The Democrats' far smaller field - three candidates as opposed to 11 - appears to be more competitive.The Democrats' far smaller field - three candidates as opposed to 11 - appears to be more competitive.
Frontrunner Hillary Clinton has a commanding lead nationally but in Iowa she is narrowly ahead of self-proclaimed Democratic socialist Bernie Sanders.Frontrunner Hillary Clinton has a commanding lead nationally but in Iowa she is narrowly ahead of self-proclaimed Democratic socialist Bernie Sanders.
Supporters of the main candidates in Iowa gave very different reasons for their backing.
Ted Cruz, said Suzanne Wood, is someone who "knows how to argue for conservative values", citing his stance on gun rights and religion.
For Julian Raven, an artist and preacher campaigning for Donald Trump, the Republican has the "courage that is required to match up with the existential threats that we face as a western civilization".
Bernie Sanders supporter Mike Bates said "he's turning out the young voters. He's like the cool grandpa", while Hillary Clinton backer Joan Pinnell said she can "personally understand the struggle that it is to be female".
Iowa has an unusual election system called a caucus, which involves people gathering at sites across the state at 19:00 local time (01:00 GMT Tuesday).Iowa has an unusual election system called a caucus, which involves people gathering at sites across the state at 19:00 local time (01:00 GMT Tuesday).
Democratic voters divide themselves into groups based on their preferred candidate but the Republican caucus process is more like a traditional ballot.Democratic voters divide themselves into groups based on their preferred candidate but the Republican caucus process is more like a traditional ballot.
The last Republican winner in Iowa who won the party's nomination was George W Bush 16 years ago.The last Republican winner in Iowa who won the party's nomination was George W Bush 16 years ago.
One issue that could have implications in Iowa is the weather.One issue that could have implications in Iowa is the weather.
The National Weather Service is currently forecasting a winter storm to strike the area on Monday night.The National Weather Service is currently forecasting a winter storm to strike the area on Monday night.
Candidates are worried that the incoming storm could prevent their voters turning out earlier in the evening.Candidates are worried that the incoming storm could prevent their voters turning out earlier in the evening.
Mr Trump joked with his supporters on Saturday, saying: "You're from Iowa! Are you afraid of snow?"Mr Trump joked with his supporters on Saturday, saying: "You're from Iowa! Are you afraid of snow?"
Iowan law mandates that it be the first "state, territory, or any other group" to select delegates in the presidential nominationIowan law mandates that it be the first "state, territory, or any other group" to select delegates in the presidential nomination
This first vote in Iowa will be followed in the weeks ahead by more ballots in the 49 other states plus US territories.This first vote in Iowa will be followed in the weeks ahead by more ballots in the 49 other states plus US territories.
Each party's nominee will be chosen by the summer, and the US will pick its next president in November.Each party's nominee will be chosen by the summer, and the US will pick its next president in November.