Hillary Clinton will end months of speculation on Sunday when she announces she is running to become the first female president of the United States, her second attempt to take the White House.
The former secretary of state, senator and first lady is expected to make the announcement on social media before she travels to Iowa and New Hampshire, two crucial early-voting states in the presidential race.
Mrs Clinton is expected to follow the announcement with a video and email message setting out the reasons why she should be the 45th president and succeed Barack Obama, the man who beat her to the Democratic nomination in 2008 with a once-in-a-generation campaign.
The 67-year-old's strong national profile and the absence of a strong Democratic rival has made the wife of 42nd US president Bill Clinton the outright favourite to win the party's presidential nomination.
Viewed as the Democrats' best hope of retaining the White House and winning a third presidential successive term, she polls way ahead, by almost six to one, of other leading Democrats: Elizabeth Warren, the anti-Wall Street senator from Massachusetts who has ruled out a run, and vice- president Joe Biden, who has yet to make a decision on 2016.
Major candidate
s Mrs Clinton joins Republicans
Ted Cruz
and
Rand Paul
, freshman senators from
Texas
and
Kentucky
respectively, as the first major candidates to announce that they are running for the presidency.
They are expected to be joined, mostly by a large number of Republican candidates, including former Florida governor Jeb Bush, son of former president George HW and brother of George W, who is seen as the favoured candidate of the Republican establishment.
A new epilogue to her 2014 autobiography Hard Choices, published on Friday, pointed to Mrs Clinton's new role as a grandmother and her belief that every American should have equal opportunities, suggesting that family values and economic equality will be two big themes of her campaign.
In an attempt to engage more with voters, Mrs Clinton's supporters said that she intended to run her presidential campaign much like her successful New York Senate race in 2000 when she embarked on a "listening tour" that helped her to win Republican districts in the state.
Concerned that, without a strong Democratic challenger to her, Mrs Clinton’s candidacy might be seen as a coronation and to counter criticism that she has a sense of entitlement, she is planning greater on-the-ground engagement with voters in Iowa and New Hampshire.
She is "in effect seeking to begin this campaign where she ended the 2008 campaign," said Democratic strategist and former Clinton aide Chris Lehane. She is "speaking to the middle class about... protecting the American Dream and doing so in venues and forums that make clear she is humbly going before them, allowing them to take her measure".
Hurt by the recent controversy over her use of a private email address for official business, a poll by Quinnipiac University on Thursday showed her slipping against Republican candidates in the swing states of Colorado, Iowa and Virginia, and in a tight race with Mr Paul.