When the campaign began last year, I was drawn to Barack Obama because he was exciting and fresh, and I instinctively compared him to Howard Dean, the anti-Iraq war candidate I had supported in 2004.

I had great regard for Hillary Clinton as well. It never occurred to me that I would meet her privately twice – or that my support could be critical to either candidate’s chance of winning the Democratic presidential nomination.

I am in the unusual position of being an undeclared superdelegate with a casting vote at the Democratic national convention in August and also one of seven uncommitted members of the Democratic party rules and bylaws committee, which met yesterday to decide on the future of disputed primaries in Michigan and Florida.

My colleagues and I have been feeling somewhat overwhelmed by the responsibility that has been placed in our hands, like the character in Isaac Asimov’s short story, Franchise, which fantasised that in 2008 elections would be decided by a single voter, chosen by computer to represent the entire country.

We’ve had to jump outside our comfort zones, talk to the media and try our best to respond to a flood of handwritten letters, phone calls and e-mails begging us to support one side or another.

We have also been heavily courted by the candidates and their high-level surrogates – congressmen, governors, campaign aides and relatives, from Bill and Chelsea Clinton to Michelle Obama. I was invited to meet Hillary Clinton for the first time in early April at a hotel in Washington with two other undecided superdelegates. She was a little late and her secret service men – burly guys with earpieces straight out of a Hollywood movie set – reluctantly allowed me to leave the building to put extra coins in the parking meter for my car.

I found Clinton to be an incredibly warm and charismatic figure. The Clinton team had clearly done their homework because, at our meeting, she praised a government agency my grandfather had helped to found in 1906.

As the national director of CasaBlanca, a project to recruit Latino Democrats, I raised the issue of immigration with her and suggested that John McCain, the Republican nominee, could be a formidable candidate among Latinos because of his willingness to take on fire from his own party on the subject. I was impressed by her solid grasp of the issues and realised I needed to do more hard thinking about which candidate to support.

A few days after her victory in the West Virginia primary, I was invited back for a one-to-one meeting with her at the national party headquarters.

After some small talk, she laid out her case for the nomination, emphasising that she would be the best advocate for Latinos and the most likely winner of key swing states against McCain. These were the kind of things that could make a guy start leaning towards a candidate. The Obama campaign had generally been reaching out to superdelegates in a lower-profile manner. However, early last week, I got a call from Bill Richardson, the governor of New Mexico, asking me to support Obama and praising CasaBlanca.

A couple of days later, I got a call from Obama himself. He stressed that it was important to find a timely resolution to the nominating process and move on to the general election, but he also wanted to make sure to extend every courtesy to his opponent.

Until now, I’ve felt that our Latino recruitment project and my role on the rules committee were important enough to warrant remaining neutral. Now that we have dealt with Florida and Michigan, I am finally free to decide whether to follow my original instincts and support Obama after all.

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