On Wednesday, the New York Times performed an election year public service with an analysis that was part history lesson and part thought exercise. Taking the example of the S&P 500 going back to Herbert Hoover, the Times rightly concluded that the Democratic Party "has been better for American pocketbooks and capitalism as a whole." But the Democrats' proven track record isn't limited to the S&P index. As history has proven time and again, Wall Street and the economy overall simply do better under Democratic presidents.
To make its case, the New York Times asked readers to imagine having put their money where its mouth is. Contrary to Republican mythology, Americans fare better - much, much better - under Democratic administrations:

As of Friday, a $10,000 investment in the S.& P. stock market index would have grown to $11,733 if invested under Republican presidents only, although that would be $51,211 if we exclude Herbert Hoover's presidency during the Great Depression. Invested under Democratic presidents only, $10,000 would have grown to $300,671 at a compound rate of 8.9 percent over nearly 40 years.

(For the eye-popping chart of the S&P's performance under each of the presidents from Hoover through Bush 43, visit here.)
As the broader record shows, the best path to prosperity is to elect Democratic presidents.
The superior performance of Democratic presidents covers virtually the entire spectrum of economic indicators. As Elliott Parker of the University of Nevada, Reno detailed in a 2006 paper, since 1949 Democratic administrations have done better than Republican ones when it comes to unemployment (5.2% to 6.0%), job creation (-.0.4% decrease in unemployment, compared to 0.3% increase), GDP growth rate (4.2% to 2.9%), and even corporate profits as a share of GDP. And to be sure, he found the Dow benefits from Democrats in the White House.
There's no shortage of studies to show that stock market returns are higher under Democratic leadership. (As it turns out, Wall Street's performance is also better when Democrats control Congress.) In 2000, Pedro Santa-Clara and Rossen Valkanov of UCLA's Anderson School of Business concluded that "that the average excess return in the stock market is higher under Democratic than Republican presidents - a difference of 9 percent per year for the value-weighted portfolio and 16 percent for the equal-weighted portfolio." As the New York Times noted of UCLA study in 2003:

"It's not even close. The stock market does far better under Democrats...
...Professors Santa-Clara and Valkanov look at the excess market return - the difference between a broad index of stock prices (basically the Standard & Poor's 500-stock index) and the three-month Treasury bill rate - between 1927 and 1998. The excess return measures how attractive stock investments are compared with completely safe investments like short-term T-bills.
Using this measure, they find that during those 72 years the stock market returned about 11 percent more a year under Democratic presidents and 2 percent more under Republicans - a striking difference."

In 2002, Slate similarly concluded that "Democrats, it turns out, are much better for the stock market than Republicans":

Slate ran the numbers and found that since 1900, Democratic presidents have produced a 12.3 percent annual total return on the S&P 500, but Republicans only an 8 percent return. In 2000, the Stock Trader's Almanac, which slices and dices Wall Street performance figures like baseball stats, came up with nearly the same numbers (13.4 percent versus 8.1 percent) by measuring Dow price appreciation. (Most of the 20th century's bear markets, incidentally, have been Republican bear markets: the Crash of '29, the early '70s oil shock, the '87 correction, and the current stall occurred under GOP presidents.)
According to almanac editor Jeffrey Hirsch, the presidential party figures are among the most significant he's found. If the stock market were random, we'd expect such a result only one-quarter of the time. "I don't know why people are convinced Republicans are good for the stock market," Hirsch says.

Why? Because Republican water carriers like Larry Kudlow and Donald Luskin continue - with great success - to perpetuate the myth that the regulation-free policies of the GOP that so benefit them personally somehow help the American people overall. (In an example of legendarily bad timing, right-wing water carrier and McCain adviser Luskin took to the pages of the Washington Post the day before the Wall Street implosion to defend Phil Gramm's assessment of the economy, calling America "a nation of exaggerators.")
So when John McCain admitted Sunday that "the economy has hurt us a little bit in the last week or two," he wasn't merely acknowledging voters' worries about his self-proclaimed economic ignorance. McCain was simply confirming what Harry Truman told Americans generations ago:

"If you want to live like a Republican, vote Democratic."