As campaigning in the New Hampshire primary elections reaches the final stages, the US Vice-President, Mr Al Gore, has been forced to clarify his stance in favour of abortion following attacks for inconsistency from his Democratic rival, the former senator, Mr Bill Bradley.
But Mr Bradley's health has also become an issue, following an interview with his doctors concerning his bouts of irregular heartbeat during his campaigning.
Mr Gore's lead in the opinion polls over Mr Bradley has narrowed over the weekend and now stands at 49 to 42 per cent. Polling in the New Hampshire Democratic and Republican primaries takes place tomorrow. Mr Bradley, who was overwhelmed by Mr Gore by two to one in the Iowa caucuses last week, badly needs a win in New Hampshire to give his flagging campaign a boost. The former New Jersey senator and basketball star has had to switch from calling for a universal healthcare system to sharpening his attacks on Mr Gore for alleged dishonesty.
The Vice-President insisted in a debate last week that he had always been consistent in his prochoice stance on abortion and in his support for the Roe v Wade Supreme Court decision in 1973 legalising abortion. But Mr Bradley is now pointing out in speeches and TV ads that Mr Gore has not been consistent.
The Bradley campaign has released letters Mr Gore wrote to constituents in the 1980s expressing anti-abortion views. In 1984, Mr Gore wrote that it was his "deep personal conviction that abortion is wrong."
"Let me assure that I share your belief that innocent human life must be protected and I have an open mind on how to further that goal," he said.
In a second letter in 1987, the then Senator Gore explained his support for a measure to prohibit federal funding for abortion except when the mother's life is in danger. "In my opinion, it is wrong to spend federal funds for what is arguably the taking of a human life."
Asked about these letters while campaigning at the weekend, Mr Gore said defensively that "I would not use that phrasing today", and insisted that he has always supported Roe v Wade.
Meanwhile, Mr Bradley and his doctors have told the New York Times that his bouts of irregular heartbeat, known medically as atrial fibrillation, should not affect his ability to be President.
But Mr Bradley acknowledged that there could be times when treatment for these spasms, which would require electric shocks under anaesthetic, would mean turning over executive powers temporarily to his vice-president under Article 25 of the Constitution.
Recent incidents of irregular heartbeat corrected themselves without this cardioversion treatment, Mr Bradley said. It is also pointed out that former President Bush suffered from this heart complaint when in office.
On the Republican side, the Governor of Texas, Mr George Bush, son of the former president, is catching up on Senator John McCain in the opinion polls. Mr McCain leads by 38 to 36 per cent, but this is within the margin of error, making it is a statistical dead heat.
Like Mr Bradley, the senator from Arizona needs a win in New Hampshire to keep his campaign alive. Mr McCain did not contest the Iowa caucuses and had built up an impressive lead over Mr Bush in New Hampshire in recent months. Now the race is seen as too close to call.
The tone has sharpened between the two men, as Mr Mc Cain's TV ads suggest that Mr Bush is not really qualified for the presidency, while Mr McCain has these qualities because of his military background and Senate experience.
New Hampshire's 738,000 registered voters deliver only 29 Democratic delegates and 17 Republican representatives to the conventions in the summer, and the state holds just four electoral votes in the presidential election.
After New Hampshire, the Republicans hold five primaries in February: in Delaware, Michigan, South Carolina and Virginia. The Democrats have a five-week pause after New Hampshire before March 7th, when 16 states hold primaries.