Fact-challenged it may be, but the vice presidential acceptance speech of U.S. Rep. Paul Ryan on Wednesday at the Republican National Convention is getting a thumbs up from a lot of folks. It did what it was designed to do – get out the message effectively against Barack Obama’s presidency, and fire up enthusiasm among convention-goers and other Republicans.

But will it go down in history as among the best political speeches ever? Not if a listing of the top 100 political speeches of the last century is a gauge. The listing, done in 1999, is the considered opinion of 137 leading scholars who were asked to recommend speeches for their social and political impact, and rhetorical artistry. Only 11 speeches from political conventions made the list. Only one was a vice presidential address – that of Democrat Geraldine Ferraro, the first female to get a major party’s vice presidential nod.

In the years since 1999, pundits and historians seem to agree that at least two other convention speeches should join the list as the best: Barack Obama’s 2004 Democratic National Convention keynote address and Sarah Palin’s 2008 vice presidential acceptance speech at the Republican National Convention where she became the first female on a GOP ticket.

Only two presidential nominees’ acceptance speeches made the grade on the listing of 100, and they were both losing candidates in the general election: Adlai Stevenson in 1952 and Barry Goldwater in 1964. That should give GOP presidential nominee Mitt Romney some comfort in any bad assessments of his speech.

A few other acceptance speeches by presidential nominees get good, if not stellar marks, by some historians including those of Franklin Roosevelt, Harry Truman, Bill Clinton and George H.W. Bush – all of whom went on to win the president’s job.

Great speeches of sitting presidents made the list: John F. Kennedy captures the No. 2 spot for his inaugural address; Franklin Roosevelt holds down the third and fourth spots for his first inaugural and for his Pearl Harbor speech; and Ronald Reagan comes in 8th for his Shuttle disaster speech (he’s also on the list five other times). Speeches of Democratic presidents are listed 24 times; speeches of Republican presidents are listed 15 times.

Those making the list of the best convention speeches were notable not only for powerful oratory but for their often courageous confrontation of divisive issues. Hubert Humphrey’s 1948 speech at the DNC was one of those.

Despite pressure from Democratic leaders, Humphrey gave an impassioned speech to put civil rights in the party’s platform, noting: “To those who say, my friends, to those who say, that we are rushing this issue of civil rights, I say to them we are 172 years late! To those who say, this civil rights program is an infringement on states’ rights, I say this: the time has arrived in America for the Democratic Party to get out of the shadow of states’ rights and walk forthrightly into the bright sunshine of human rights!” The civil-rights plank was adopted.

Jesse Jackson’s soaring convention oratory was on the 100 best twice – in 1984 and in 1988 when he ran for president. Ted Kennedy made the list for his 1980 DNC speech, when he lost the party’s nomination to Jimmy Carter, who ran and lost a bid for a second presidential turn.

It’s the stellar keynote convention speeches that are often remembered. Obama’s in 2004 paved the way for a little-known U.S. senator to make a successful run for president four years later. Both Mario Cuomo’s in 1984 and Ann Richards’ in 1988 came in years the Democrats lost the presidential race but have survived for their passion and rhetorical excellence.

But it’s Congresswoman Barbara Jordan whose 1976 DNC keynote has become the standard by which all others are judged. It was the only convention keynote speech that made the top 10 in the scholars’ ranking, coming in at No. 5. Jordan’s powerful oratory – eloquent and masterful in delivery and substance – put her among the best, they said.

New Jersey Gov. Chris Christie got his shot this week to join the best keynoters with his Tuesday address to the RNC. San Antonio Mayor Julian Castro will get his shot at the Democratic National Convention next week. Both Christie and Castro are being touted as future presidential nominees. Could a good speech really aid that ascent? Ask Barack Obama.