A look back at market performance as measured by the Dow Jones Industrial Average across 18 administrations since Franklin Roosevelt suggests that using such political equations to predict financial markets is, well, mostly bull. As presidential candidate Bill Clinton once put it, it's the economy, stupid.

Consider the presidents who have presided over bull markets. The single longest bull run in U.S. history has taken place under Democrat Clinton, when the Dow has more than tripled since the day he took office. The stock market's next best performance came during the three terms of fellow Democrat Franklin Delano Roosevelt, when the Dow nearly tripled, rising from 54 to 158.

But third place goes to Republican Ronald Reagan, who presided over a 135 percent rise in the Dow, while another Republican, Dwight D. Eisenhower, takes fourth place with a 120 percent gain. Somewhat less dramatic but still in the plus column are Democrats Harry Truman (82 percent), John Kennedy and Lyndon Johnson (47 percent), and Republican George Bush (45 percent).

Bear markets also seem blind to which party controls the White House. Republican Richard Nixon watched the Dow dive in 1973, thanks to sharply rising oil prices and a recession. Toss in Watergate and Nixon's resignation, and by the time his successor Gerald Ford left office in 1977, the Dow was only about 1 percent higher than it was when Nixon took office in 1969. Over the course of Democrat Jimmy Carter's presidency, when the economy was plagued by double-digit inflation and unemployment as well as the Iranian hostage crisis, the Dow actually fell by about 1 percent.

So what do the bull market presidents have in common? Certainly not political parties. What they do share, however, is timing: Each took office after a period of severe economic - and sometimes political - strain, which had helped depress financial markets. Add to that some deft economic policy choices early in their administrations, and each also presided over an economic and financial comeback.

Timing is Everything
For example, FDR followed the Great Depression; his New Deal and later World War II helped restore the battered economy and financial markets. Eisenhower took office at the end of World War II, when the return of millions of young men from the battlefields of Europe and the Pacific would fuel a tremendous economic boom. Reagan's tax cuts and deficit spending - along with a tough-minded Fed - helped jolt the economy out of its Carter-era stagflation. Of course, the economy - and Bush - later paid a high price for the Reagan deficits, but in the short term the economic stimulus they provided helped get the economy and markets moving again.

So what does the past suggest for the new president, whoever he may be? Are things too good to go anywhere but down?

Not necessarily. After all, the economy and the market have settled down this year, thanks largely to six Federal Reserve Board interest rate hikes. It looks like the Fed may be finished with rate hikes for a while, paving the way for continued growth, though probably not at the same robust pace as we've seen in recent years. Add to that the explosion of innovation in New and Old Economy companies spurred by the Internet, the growth of capitalism around the globe, the likelihood of rising U.S. budget surpluses and the new individual investment incentives no matter who is president, and there is still reason for optimism.

Of course, it's always possible that policy mistakes on the part of a new president could upset that delicate balance. But fiscal excesses are likely to be checked by continued divided government in Washington. "If you were to see the Democrats get control of Congress and the White House, that might spook the markets," says Invesco chief investment office Tim Miller. "But short of that, I don't see a material near-term impact from the elections on the overall market."

So don't get too distracted by the presidential race. Sure, the choice may make important differences for individual sectors of the market. But history suggests it's the economy - not which party wins the presidency - that will drive the markets overall.