“Thrown under the bus” is becoming the phrase of the American presidential election. It describes the moment when a candidate disowns an embarrassing supporter or adviser.

Campaign camp-followers can find themselves staring at the dreaded underside of the bus for any number of reasons. Barack Obama, the probable Democratic party candidate, committed the most famous act of bus-related violence when he finally disowned the Rev Jeremiah Wright – his spiritual mentor. John McCain, the Republican candidate, has had to rid himself of various advisers who were too close to lobbyists.

Two recent incidents illustrate that making controversial remarks about Israel is particularly risky.

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I am just coming to the end of a week in Washington. Now that it seems pretty certain that the presidential race will be McCain v Obama, political gossip is turning to the second-order questions – who will be the vice-presidential candidates? Who will get the big cabinet jobs?

Barack Obama will be even less inclined to want Hillary Clinton on his ticket, after her tasteful suggestion that he might be assassinated – like Bobby Kennedy. The thought of having Bill hanging around the Obama White House is also not obviously attractive. Still, Hillary seems to want the job – and could yet force Obama’s hand. The Obama camp are desperate to unify the party and get on with battling McCain. What if Hillary threatened to take the fight all the way to the Democratic convention at the end of August – and even to make a speech there, arguing that Obama is unelectable and appealing to delegates to switch over to her camp?

And her price, for avoiding this nasty scenario? Why, the second spot on the ticket.

I chaired a debate at the US embassy in London last night on the impact of the internet on the presidential election. It was surprisingly interesting. If you have a lot of time on your hands, you can watch it here.

One of the reasons I found the discussion interesting is that it convinced me that there is more to the subject than I had realised. I started fairly sceptical. I don’t think it’s very obvious that the internet has made this election qualitatively different from all other campaigns.

But here are two interesting facts that I gleaned that have made me re-consider – a bit. First, 5.5 million people have watched all 35 minutes of Obama’s Philadelphia speech on race on YouTube. In an age when the average TV news sound-bite is down to 12 seconds, this is extraordinary and heartening.

Second, the internet has transformed American campaign finance – and may have solved one of the biggest problems with American democracy. The problem – as we all know – is that elections are so expensive that candidates have to spend huge amounts of time raising funds; and have to warp their positions to suit the prejudices of wealthy donors. But Obama has already raised around $300m in small donations via the internet; vastly more than Hillary who has – by and large – raised money in the traditional way. One of last night’s panellists reckons that by the end of the election, Obama might have raised up to $1 billion on the net.