If public interest is any indicator, Barack Obama is well ahead of the last two Democratic presidential candidates, Al Gore and John Kerry, in his race for the White House.

Obama’s Thursday speech, in which he accepted the Democratic nomination for president, drew the biggest audience for a Democratic speech in at least 12 years and perhaps ever, since Nielsen only began keeping detailed nightly records in 1996.

Some 38.4 million total viewers tuned in across 10 networks for the speech, in which Obama became the first major-party black presidential nominee in U.S. history. Certainly the historic nature of his speech, delivered 45 years to the day after Martin Luther King Jr.’s “I Have a Dream,” drew in more viewers than would have usually tuned in for the convention.

The speech was carried from roughly 10 to 11 p.m. Thursday on ABC, CBS, NBC, CNN, Fox News Channel, MSNBC, Univision, Telemundo, BET and TV One, the two latter networks aimed at African Americans and making their first forays into convention coverage.

The past two Democratic convention acceptance speeches have drawn significantly lower crowds, though Nielsen had included only six networks in 2004 and 2008. Like BET and TV One, the Hispanic networks are new to the measurement this year. Also, previous years included only live viewing, while this year’s numbers include live-plus-same-day DVR playback.

Kerry’s 2004 acceptance speech averaged 24.4 million viewers, while Gore’s 2000 performance averaged a mere 21.8 million.

An estimated 84,000 turned out in person to watch Obama accept the nomination at Denver’s Invesco Field.

For the four-night convention, the 10 networks averaged 30.2 million viewers, again well up from 24.4 million four years ago and 20.6 million eight years ago.

But whether Republicans see a similar boost this week may be tempered by real-life events. Presumptive nominee John McCain ordered a pull back on convention events as Hurricane Gustav threatened the Gulf Coast just three years after Katrina ravaged New Orleans and surrounding areas.

Some Republicans from the threatened areas canceled planned appearances at the convention as citizens were evacuated. President Bush, who was supposed to speak in person but instead headed to Texas to oversee preparations, said he may address conventioneers via satellite tonight.