There is a rapidly congealing consensus about Hillary Clinton among Democrats. The first is that it’s hard to see how she can be stopped from becoming the party’s nominee for president in 2008. The second is that nobody really wants her to be the nominee.

If this sounds familiar, it is. The Democrats had exactly the same feelings about their last two nominees, Al Gore and John Kerry. They both lost, of course, although there will always be an asterisk next to the name Gore on that one.

Most Democrats I know also fear that, at an unusually propitious time for their party, Hillary could lose the White House for them again as well. In almost every straw poll she loses big to potential rivals such as John McCain and Rudy Giuliani. About a third of the country already strongly disapproves of her. Unlike McCain and Giuliani, her unfavourable ratings actually beat out her favourable ones. And that’s after five years of very careful and very good PR.

The inevitability argument for Hillary is a strong one. In some ways she is now following George W Bush’s tack in 2000. She has amassed way more money than any of her rivals — more than $40m at the last count — and has a nepotistic connection to the last president in her own party. Her name recognition is through the roof. She lives in that rare pantheon of women whose global reach overwhelms the need for any surname: Diana, Oprah, Madonna, Condi, Hillary. In the latest polls of Democrats, Hillary is favoured by 38% of potential primary voters. Kerry is second with 14%.

Chuck Todd, editor of Washington’s Hotline put her position thus: “Frankly, to call her an 800lb gorilla would be underselling her.” While any woman might prefer a slightly more flattering analogy, you can see his point. The task of taking her on might seem gargantuan to a little-known former state governor such as, say, Mark Warner of Virginia.

She has behaved, meanwhile, as a very shrewd senator, diligently tending to her constituents, especially in conservative upstate New York, while running around the country raising money for local parties and candidates. Her Senate opponent in New York state this November is a no-hoper and so Hillary can keep her exchequer well funded for the presidential run. She has positioned herself as a hawk on national security, recently pronounced the president “charming” and “good company” and has established detente with Rupert Murdoch, chairman and chief executive of the company that owns this paper as well as New York city’s feistiest tabloid, the New York Post. She is doing all the right things. And she would add the glamour and excitement of being the first woman president of the United States.

Where’s the catch? Catch No 1 is that Americans, by and large, don’t like her and don’t want to intensify the culture wars that have already ripped the country apart. More than any other single figure, Hillary represents one side in that war, fairly or unfairly.

She could ramp up Republican fundraising just by emerging as the nominee. She could single- handedly breathe new life into the religious right’s now demoralised base. No sane person wants to go back to the 1990s on that front.

That is why the relatively fresh face of McCain appeals. He may be old but the idea of a McCain presidency — bipartisan, maverick, straight-talking, frank — is new and appealing. That is one reason why his favourables easily defeat his unfavourables 65 to 18.

The Democratic left also suspects Hillary. Markos Moulitsas, grand pooh-bah of the influential Daily Kos communal blog site, recently wrote in The Washington Post of the Democratic frontrunner: “She doesn’t have a single memorable policy or legislative accomplishment to her name. Meanwhile, she remains behind the curve or downright incoherent on pressing issues such as the war in Iraq. On the war, Clinton’s recent ‘I disagree with those who believe we should pull out and I disagree with those who believe we should stay without end’ seems little different from Kerry’s famous ‘I actually did vote for the $87 billion before I voted against it’ line. The last thing we need is yet another Democrat afraid to stand on principle.”

The more Hillary tries to triangulate like her husband, the more the left of the party gets restless. Been there, done that, it grumbles. Then there is her husband. What on earth do you do with him? He’s not exactly going to be content as a traditional first lady, arranging state dinner invitations and redesigning the Oval Office rug. In a Hillary presidency we would essentially have an unconstitutional third term for Bill as co-president, with all the psycho-drama and mellifluous, undisciplined talent that implies. I’m not sure that Americans are quite ready for another eight years of that.

Strangely, the big public mood swing against the Republicans and Bush may hurt Hillary as well. If the Democrats retake the house or Senate or even both this November, it makes it less likely for a Democrat to retake the White House in 2008. Why? Because voters have seen what united government does. Whether it’s a Democratic house, Senate and president or a Republican house, Senate and president, the result is always massive spending, creeping corruption, over-reach and arrogance.

The best periods of government in America in recent times have been when president and Congress were in different hands: Reagan with the Democrats in the 1980s, Clinton with the Republicans in the mid-1990s. The better the Democrats do in 2006, the worse a Democratic presidential candidate may do in 2008.

Hillary, moreover, may be one nepotistic step too far. Americans are sick of dynasties and to have potentially 28 continuous years of presidents from two single families begins to make the United States look like a banana republic or a Tudor and Stuart pas de deux. I’m not just thinking of the terrible task that future students are going to have, trying to remember which Bush and which Clinton came when and did what; I mean simply that in a country of 300m, we really should be able to look beyond two families for leadership talent.

Which Democrat will take Hillary on? They need to make a hard decision between now and Christmas. And have a lot of guts.

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