Who will be Barack Obama's Lyndon Johnson?

Because of his youth, his liberal idealism and his charisma, Barack Obama has been compared to John F. Kennedy. On Jan. 27, of this year Kennedy's daughter Caroline endorsed Obama in a column in the New York Times, writing that she has "never had a president who inspired me the way people tell me that my father inspired them. But for the first time, I believe I have found the man."

What Caroline Kennedy and other enamored Democrats shouldn't forget is that Jack Kennedy won the 1960 election by fewer than 113,000 votes out of a total of more than 68 million cast. Voters may have felt inspired by Kennedy once he was president, but they may also have felt uneasy about voting for him for three reasons - he was young, he was an aristocrat, and he was unprecedented.

Kennedy was not only the youngest president in the history of the United States, he was the first president who was not a Protestant. Back then, that was a bigger deal than it would be today. The United States has always been a Protestant-majority country, though the nation is showing signs that it will drop below the 50 percent mark soon. And while anti-Catholic sentiment may not have influenced a majority of voters in 1960, it was probably at least as prevalent as anti-black sentiment is today.

Kennedy's youth gave voters uneasy about his religion an excuse to oppose him - he wasn't "experienced enough" to be president. Barack Obama faces the same hurdle. Voters who feel uneasy about his general foreignness, but equally uneasy about feeling that way, have plenty of excuses not to vote for him - and opt instead for the safe, familiar choice: John McCain.

Kennedy overcame voters' uneasiness about his background, and managed to just barely defeat the safe, familiar choice (Richard Nixon), largely by picking the right running mate. While Kennedy was from the east coast, Catholic, wealthy-liberal wing of the Democratic Party, his running mate - Lyndon Johnson - represented the Middle American, Protestant, beer-drinking wing.

Johnson had a reputation as a tough guy famous for arm-twisting fellow politicians. He was a good-old boy, the kind of guy who exuded the earth of America. Where Kennedy's youth and religion were unsettling, and his elitist background made him repelling, Lyndon Johnson provided reassurance. That's exactly what Barack Obama needs from his running mate.

Not only is Obama young, like Kennedy; not only does Sen. Obama lack any executive experience, just like Sen. Kennedy did; not only does Obama's Kennedyesque background (international youth, educated at Harvard) make the lower-income voters that any Democrat needs to win an election wonder whether he's really "their man;" and to top everything, he'd be the first president who is black. All that forces America to make a historic gut-check in the voting booth. Where John McCain offers voters plenty of reassurance, Barack Obama - just because of who he is - demands that voters walk out on a limb. It's exactly the kind of decision the Democratic candidate doesn't want voters to have to make in November.

The ideal running mate for Obama would have three qualities: he would be white, male and tough enough to counter John McCain's national security credentials. The Democratic Party has two ideal candidates that fit that bill precisely - retired four-star General Wes Clark, and Silver Star-wearing former U.S. Marine Jim Webb.

Like Kennedy in 1960, Obama's choice of running mate could well be the determining factor in the outcome of this election. Once he's president, Obama can dazzle the nation with his oratory, he can reach across the aisle by proposing sensible policies and toning down the partisan rhetoric, and he can prove that he's up to the job by performing well in office. But before he has a chance to do any of that, he has to convince the general public that voting for him is not a risk.

Having a running mate who is more "experienced" would not necessarily be an advantage for Obama. A lifetime spent in Washington does not make a politician more appealing to the electorate. If that were the standard, Dick Cheney would be the front-runner in November. What voters are looking for is a candidate who can both bring the change that they want and who is reassuring. That's where McCain's appeal comes from - he's clearly not Bush, but he's also not Barack Hussein Obama.

The fact that General Clark has never been elected to any office, and that Sen. Webb is serving his first term in the U.S. Senate, make them both stronger candidates as running mates. They would bring all of the advantages of a tough white guy on the ticket, while reinforcing Obama's central appeal - that he's an outsider who can bring change to the nation's politics. The fact that neither Webb nor Clark have any ties to the Clinton administration also reinforces the ticket's appeal to Republicans and Independents.

By picking Obama to be their nominee, Democrats have strengthened themselves in the West (including in the state where they are holding their convention, Colorado). But they have also increased their risk of losing some important swing states in the East. The post-industrial Lake Erie belt of Michigan, Ohio and Pennsylvania accounts for over ten percent of the electoral vote, and Obama lost all three states by wide margins in the Democratic primaries. All three were swing states in the last two elections - in 2004, the Democrats carried Michigan and Pennsylvania by less than three points, and lost Ohio by less than two.

However, in 2006, Democrat Sherrod Brown won 56 percent of the Senate vote in Ohio while fellow Democrat Bob Casey won 59 percent of the vote in Pennsylvania. Democrats won in five Ohio and Pennsylvania Congressional districts that had previously been considered safely Republican. Both U.S. Senators from Michigan are already Democrats. With anti-Iraq War sentiment in all three of the Lake Erie swing states strong, the party is clearly on the rise in the region. Obama simply needs to pick a running mate who makes voters who were already leaning towards the Democrats feel comfortable doing so.

The right kind of ticket can carry Obama to the White House. If Obama wins in the states bordering Lake Erie, he will be the next president of the United States. To achieve this, he needs to do what Kennedy did in 1960 - pick a running mate who reassures voters.

The purpose of a running mate is to win the general election. Don't pick another you, Mr. Senator. Pick the 2008 equivalent of Lyndon Johnson.