Barack Obama has said he is now within reach of becoming the Democratic candidate for the US presidency.
Barack Obama has said he is now within reach of becoming the Democratic candidate for the US presidency.
Mr Obama says he has a majority of pledged delegates - won in primary elections - who choose the nominee.
Mr Obama has a majority of "pledged" delegates, who are won in primary elections, although he is still short of a confirmed overall victory.
His claim came as his rival Hillary Clinton won Kentucky's Democratic presidential primary by a large margin and vowed to fight on.
US media have projected a win for him in Tuesday's Oregon primary.
Results are expected shortly from the Oregon primary, where surveys suggest Mr Obama will win.
But his key rival Hillary Clinton has won Kentucky's Democratic presidential primary by a large margin and vowed to fight on.
'Popular vote'
'Popular vote'
Mr Obama chose to address his supporters on Tuesday night in Iowa, scene of this year's first presidential selection contest.
Mr Obama chose to address his supporters on Tuesday night in Iowa, scene of this year's first presidential selection contest.
"We have returned to Iowa with a majority of delegates elected by the American people," he told his supporters.
"We have returned to Iowa with a majority of delegates elected by the American people," he told his supporters.
DEMOCRATIC DELEGATES Total delegates (pledged and super-delegates) needed for nomination: 2,026Total pledged delegates at stake: 3,253Total super-delegates at stake: 797Total delegate tally for Barack Obama: 1,925Pledged delegate tally for Mr Obama: 1,618Total delegate tally for Hillary Clinton: 1,750Pledged delegate tally for Mrs Clinton: 1,471 Source: Associated Press, as of 0100 BST on 21 May
DEMOCRATIC DELEGATES Total delegates (pledged and super-delegates) needed for nomination: 2,026Total pledged delegates at stake: 3,253Total super-delegates at stake: 797Total delegate tally for Barack Obama: 1,940Pledged delegate tally for Mr Obama: 1,633Total delegate tally for Hillary Clinton: 1,759Pledged delegate tally for Mrs Clinton: 1,480 Source: Associated Press, as of 0420 BST on 21 May
"You have put us within reach of the Democratic nomination for president of the United States," he added.
"You have put us within reach of the Democratic nomination for president of the United States," he added.
Hailing her Kentucky victory, Mrs Clinton said she would fight "until we have a nominee - whoever she may be".
Hailing her Kentucky victory, Mrs Clinton said she would fight "until we have a nominee - whoever she may be".
Speaking to her supporters, Mrs Clinton said: "It's not just Kentucky bluegrass that's music to my ears, it's the sound of your overwhelming vote of confidence, even in the face of some pretty tough odds."
Speaking to her supporters, Mrs Clinton said: "It's not just Kentucky bluegrass that's music to my ears, it's the sound of your overwhelming vote of confidence, even in the face of some pretty tough odds."
And in a passage seemingly directed at the remaining undecided super-delegates - the party elders who get an automatic vote at the party's nominating convention - Mrs Clinton argued that she would be "best positioned to win in November" against Republican candidate Sen John McCain.
And in a passage seemingly directed at the remaining undecided super-delegates - the party elders who get an automatic vote at the party's nominating convention - Mrs Clinton argued that she would be "best positioned to win in November" against Republican candidate Sen John McCain.
Barack Obama's Oregon victory speech
Mrs Clinton also said she was "winning the popular vote" over Mr Obama.
Mrs Clinton also said she was "winning the popular vote" over Mr Obama.
The claim has been questioned by the Obama campaign, which argues that Mrs Clinton's popular vote calculation includes disputed contests in Michigan and Florida, and does not include results from several caucus states in which Mr Obama did well.
The claim has been questioned by the Obama campaign, which argues that Mrs Clinton's popular vote calculation includes disputed contests in Michigan and Florida, and does not include results from several caucus states in which Mr Obama did well.
Barack Obama claims election milestone
Mr Obama hopes his pledged delegate majority will encourage the remaining undecided super-delegates to back him.
Mr Obama hopes his pledged delegate majority will encourage the remaining undecided super-delegates to back him.
In Kentucky, Mrs Clinton won 65% of the vote to Mr Obama's 30%.
In Kentucky, Mrs Clinton won 65% of the vote to Mr Obama's 30%.
Voters in Oregon, which has a mail-in voting system, have until 2000 local time (0300 GMT) to return their ballots to election offices.
Voters in Oregon, which has a mail-in voting system, had until 2000 local time (0300 GMT) to return their ballots to election offices.
Mrs Clinton has warned Mr Obama against declaring premature victory, saying it would be a "slap in the face" to her millions of supporters so far and those states yet to vote.
Mrs Clinton has warned Mr Obama against declaring premature victory, saying it would be a "slap in the face" to her millions of supporters so far and those states yet to vote.
'Next challenge'
'Next challenge'
Mr Obama's aides are increasingly pushing the message that he has all but wrapped up the Democratic nomination and will be the one to face Mr McCain in November's general election.
Mr Obama's aides are increasingly pushing the message that he has all but wrapped up the Democratic nomination and will be the one to face Mr McCain in November's general election.
Hillary Clinton's victory speech in Kentucky
Hillary Clinton's victory speech in Kentucky
"As we near victory in one contest, the next challenge is already heating up," campaign manager David Plouffe wrote in an e-mail to supporters on Monday.
"As we near victory in one contest, the next challenge is already heating up," campaign manager David Plouffe wrote in an e-mail to supporters on Monday.
"President Bush and Senator McCain have begun co-ordinating their attacks on Barack Obama in an effort to extend their failed policies for a third term."
"President Bush and Senator McCain have begun co-ordinating their attacks on Barack Obama in an effort to extend their failed policies for a third term."
BBC North America editor Justin Webb says Mr Obama wants to suggest without quite saying so that the primary season is closing and the general election race is beginning.
BBC North America editor Justin Webb says Mr Obama wants to suggest without quite saying so that the primary season is closing and the general election race is beginning.
Our correspondent adds that although Mrs Clinton insists the race is still on, the truth is that the undecided super-delegates are moving steadily towards Mr Obama, with six more added on Monday according to the Associated Press news agency.
Our correspondent adds that although Mrs Clinton insists the race is still on, the truth is that the undecided super-delegates are moving steadily towards Mr Obama, with six more added on Monday according to the Associated Press news agency.
Once the 103 pledged delegates at stake in Kentucky and Oregon have been divided between the two rivals, Mr Obama may be only 50 to 75 short of the 2,026 delegates needed, AP says.
Once the 103 pledged delegates at stake in Kentucky and Oregon have been divided between the two rivals, Mr Obama may be only 50 to 75 short of the 2,026 delegates needed, AP says.
Mr McCain, senator for Arizona, has already begun targeting Mr Obama as his probable opponent in November.
Mr McCain, senator for Arizona, has already begun targeting Mr Obama as his probable opponent in November.
Monday saw him criticise Mr Obama over comments he made a day earlier suggesting that Iran does not pose the same level of threat to the US as the former Soviet Union once did.
Monday saw him criticise Mr Obama over comments he made a day earlier suggesting that Iran does not pose the same level of threat to the US as the former Soviet Union once did.
In response, Mr Obama said that while Iran was a "grave threat", it had no nuclear weapons whereas the Soviet Union "had thousands".
In response, Mr Obama said that while Iran was a "grave threat", it had no nuclear weapons whereas the Soviet Union "had thousands".
Are you in Kentucky or Oregon? Are you voting on Tuesday? Do you think the outcome of these primaries will decide the Democratic race? Send us your comments using the form below.
Are you in Kentucky or Oregon? Are you voting on Tuesday? Do you think the outcome of these primaries will decide the Democratic race? Send us your comments using the form below.
