Let me first take this opportunity to thank Josh Marshall, Lila Shapiro and all the folks at TPM for giving me the opportunity to talk about Live From the Campaign Trail. It's always humbling to be asked to write about presidential politics; but even more humbling to be asked by the best political blog on the web.

One of the reasons I wrote this book was because I believe that presidential campaigns are actually far more substantive than we generally assume - and that great campaign oratory is not only the best evidence of this phenomenon but is a key element of the success or failure of a presidential candidate. Luckily for my thesis, Barack Obama decided to run for President in 2008.

However, along with Obama's meteoric political rise have come some rather pointed questions about the power of campaign speechwriting - is Obama getting by on his great felicity with rhetoric while glossing over substance? Are his campaign speeches "just words" as some McCain supporters (and former Hillary Clinton backers) like to assert? Beyond the more direct questions about Obama's skills as a speechgiver, there are deeper questions to examine: can Obama's fundamentally affirmative campaign message overcome the recent negative attacks from John McCain that have tightened up the race? And, are campaigns actually less substantive than I assume and do TV ads, debate performances, even GOTV operations make the real difference on Election Day - and not campaign oratory?

These are all legitimate questions and I hope that we can touch on them this week; but they tend to miss a larger truism about great oratory - words matter in speeches; but ideas matter a lot more, especially on the campaign trail.

The effectiveness of Obama's speeches is not rooted in the beauty of his words but instead is his ability to put forward political ideas that resonate with the American people. Obama's political ascendancy is paved by a narrative and message of political change that is simply more compelling than the offerings of his opponents.

Think about the greatest American speeches. We remember MLK's call for a society where his children would be judged not by the color of the skin but by the content of their character not necessarily for its powerful symbolic imagery but the way it paints an idyllic vision of racial reconciliation grounded in the most basic and egalitarian of American values.

Schoolchildren memorize the Gettysburg Address not because Lincoln's words were so evocative, but because the idea that "government of the people, by the people, for the people, shall not perish from the earth" changed the very way that we, as Americans, think about our country.

At its core, a great speech is a combination of stirring words and powerful ideas. This is particularly true on the campaign trail where great oratory tends to grab listeners by the heart and the head and put their jumbled feelings about America into an inspiring and coherent narrative.

The most memorable campaign speeches capture the specific desires of the American people, offering a generally affirmative vision of where a candidate wants to take the country.

In 1932, Franklin Roosevelt pledged a "New Deal" for the American people calling for "bold, persistent experimentation" in government. That idea of activist government, in contrast to the status quo policies of Hoover, was ultimately responsible for FDR's victory in November - certainly more than the modern welfare state that FDR's presidency birthed.

In 1980, Ronald Reagan campaigned against the excesses of liberalism and the failures of the incumbent President, Jimmy Carter, but he also staked his candidacy on a pledge to "make America great again" offering voters an optimistic vision of where a Reagan presidency would take the country.

In 1992, Bill Clinton pledged under his Presidency the middle class would be forgotten no more and at a time when Americans were concerned about the direction of the country he told them that he still optimistically believed "in a place called Hope." The weak economy and unpopular incumbent President were helpful to Clinton but so too was the sense that he was a different kind of Democrat who would bring genuine change to Washington.

Of course, influential campaign speeches are not always been about political change. In 1968, Richard Nixon portrayed himself as the voice of "forgotten" America and "the non-shouters, non-demonstrators" who would later become known as the silent majority. Considering the chaos of the year, a pledge to restore order and promising to slow down change in America was far more powerful than Nixon personally, who was still distrusted by millions of his countrymen.

So what about Obama and McCain on the stump? Stylistically, there is no comparison: as a speechgiver, Obama is far better than McCain.

But I would argue Obama is defeating McCain on substance points as well - and it explains why he is the nominee of his party and why he has a significant advantage going into the Fall election.

Think for a second about Obama's key campaign message - "change we can believe in." Whether you like Obama or not, the change-element of his campaign and its relatively non-partisan nature, whether its about ending the war in Iraq or transforming the culture of Washington, is fairly clear.

With McCain it is not easy to pinpoint any affirmative message that he is peddling. Commentators have focused on McCain's disastrous speech in New Orleans because of its putrid green background, but the speech was a failure not because the stagecraft was poor but because the words themselves were uninspiring and unaffecting. There was no overarching message from McCain except 'the other guy is worse than me.'

John McCain has yet to positively define his campaign; focusing instead on the iniquities of his opponent. But even in the most harshly negative campaigns such as Bush in 1988 or his son in 2004 both candidates generally offered a more compelling vision for their presidencies than their opponents did. (Harry Truman's 1948 run for the White House is the one major exception to this rule.)

Making matters worse for McCain is that 1988 and 2004 were not change elections - and 2008 most certainly is. And in every great change election, whether it was 1932, 1960, 1968, 1980 or 1992, Americans have been given two very different narratives about America: liberalism vs. conservatism, a muscular vision of foreign policy vs. a more restrained one; change vs. the status quo. Right now Barack Obama is not only more in tune with Americans on all three of these issues, but he is providing voters with a more hopeful political narrative for the future. John McCain is not and until he does, it is going to be a difficult campaign for him to win. As the old saying goes, you can't beat something with nothing.

Of course, there is a flip side to this argument and one that is now receiving a great deal of currency - namely that Obama's high-minded rhetoric risks alienating working class Americans and creates an opening for a more plain-spoken candidate such as McCain. We've seen this phenomenon in recent days with McCain's 'celebrity' attack ads against Obama that seem to be gaining traction. I'm of the view that these not only won't work but will ultimately backfire because in a change election people are not only looking for a more positive campaign message, but they are more willing to take a chance on a relatively unknown candidate. I would be curious to hear if my colleagues agree or do they think I am showing too much confidence in voters to embrace Obama's largely hopeful message. And am I underplaying the effectiveness of McCain's negative attacks on Obama and overplaying how influential his speeches will be in motivating swing voters, even in a race where Democrats should be favored?

If that isn't enough I would be curious to hear from my colleagues what they think has been the best speech on the campaign trail this year and why. I would argue that it was not Obama's race speech, but instead his remarks after winning the Iowa caucus, which brilliantly captured his key campaign themes - certainly more than his race speech, which was largely a defensive effort to neutralize the Jeremiah Wright issue.

Hopefully that will be enough to get us started.