Prominent Democrats have cracked open the door for Joe Biden, the US vice-president, to enter the race for the Democratic presidential nomination, amid growing concerns over the viability of Hillary Clinton's candidacy.
Speculation grew yesterday that Mr Biden may soon challenge Ms Clinton for the Democratic nomination as the vice president met with Senator Elizabeth Warren, a power broker among more liberal Democrats.
The move follows the resurfacing of the long-running row over Ms Clinton's use of a private email account while serving as secretary of state.
It has emerged that top secret material may have been transmitted during her use of the email account, which is now subject to an FBI investigation.
On Sunday, California governor Jerry Brown said the email saga carried a "dark energy" that represents a substantial challenge for Ms Clinton's campaign.
"It is almost like a vampire. She is going to have to put a stake ... in the heart of these emails," Mr Brown added.
Asked if Mr Biden should run, Mr Brown replied: "If I were Joe Biden, I would probably give it very serious consideration."
Ms Warren, who has strong support from liberal groups that would be critical to winning in early voting states, has said she will not run for president herself, but she has not endorsed Ms Clinton or any other Democratic candidate.
Josh Alcorn, a senior adviser for Draft Biden 2016, a group that is laying groundwork for a potential run, said the vice-president was "sounding out people in early (primary election) states, activists and potential supporters".
Mr Biden is gearing up for a packed September schedule in his day job that could showcase him as the politician best poised to carry on US President Barack Obama's policies, or open him up to new lines of attack if he stumbles.
These include mid-September votes in Congress on an Iran deal that Mr Biden has been deeply involved in promoting; a looming budget showdown; and administration efforts on climate change, criminal justice reform and closing the terrorism detention facility at Guantanamo Bay, Cuba.
While Biden aides said he hasn't made a decision, the accelerated pace of his deliberations over the course of the last two weeks are being read as signals by his supporters that he is edging closer to a run. (© Daily Telegraph, London)
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