CLEVELAND — Many different combinations of states could lift President Bush or Sen. John F. Kerry to the 270 electoral votes needed to win the White House.
But the one scenario some insiders on both sides consider the most likely features six states, split into groups of three.
These strategists and operatives agree that either candidate will be very tough to beat if he can win two of the three largest battlegrounds -- Florida, Pennsylvania and Ohio -- and two of the three Upper Midwest states still in play -- Minnesota, Iowa and Wisconsin.
In 2000, Bush carried two of these states: Ohio and Florida. Democrat Al Gore won the other four. Today, all six appear within reach for either Bush or Kerry.
Fittingly for an election that has defied many expectations, the electoral math is complicated, with both sides looking at any number of combinations that get their candidate to 270 electoral votes. And political analysts talked about possible election day surprises in such states as Democrat-leaning Hawaii or GOP-tilting Colorado.
But figuring prominently in the calculations by both sides are the three major battleground states and the three Upper Midwest states.
If either candidate sweeps Florida, Ohio and Pennsylvania, with a combined 68 electoral votes, he is virtually certain to win, absent a big surprise elsewhere, such as Michigan moving to Bush. If no one takes all three, the three Upper Midwest states, with a combined 27 electoral votes, could decide the race -- with Wisconsin the most hotly contested among them.
Here is a voter's guide to some of results the experts will be studying to glean the trends in these six states:
Florida
(27 electoral votes)
Jim Kane, executive director of the nonpartisan Florida Poll, said Kerry's performance in the Democratic bastion of South Florida should provide a clear indication of his statewide prospects. Four years ago, in the wake of the furor over the federal government's decision to return young Cuban refugee Elian Gonzalez to his father in Cuba, Gore carried Miami-Dade County by about 70,000 fewer votes than President Clinton had in his 1996 reelection victory.
Kane predicted that for Kerry to carry Florida, he "needs to exceed the Gore margins in South Florida," which also includes Broward and Palm counties.
To prevent that, Bush aides hope he matches the 46% share of the vote he got in Miami-Dade.
The other key is the state's concentration of swing voters in the heavily suburban counties along the Interstate 4 corridor from Orlando to Tampa.
In 2000, Orange County (Orlando) tilted from virtually dead-even in the 1996 election to a slight Democratic majority. But Hillsborough County (Tampa) gave Bush about an 11,000-vote majority after narrowly backing Clinton four years earlier.
"If Hillsborough switches back to Kerry," said Kane, "that's a significant change."
Republicans also want to drive up Bush's lead among conservative voters in the Florida Panhandle, exceeding the 32,074-vote margin Bush amassed in Escambia County.
"If we came out again with [that] margin in a [vote] where there is 10% more turnout, that would be bad for us," said one senior Bush campaign aide.
Pennsylvania
(21 electoral votes)
For both sides, the math starts in Philadelphia and its suburbs.
In 2000, Gore came out of Philadelphia County with a nearly 350,000-vote advantage; this time, Democrats are hoping to push that to 400,000, said G. Terry Madonna, a political scientist at Millersville University.
Just as important are the surrounding suburban counties, which tilted from reliably Republican during the 1970s and 1980s toward the Democrats under Clinton. In 2000, Gore carried Bucks, Montgomery and Delaware counties by a combined 9 percentage points.
If Kerry matches or exceeds that, "Bush probably can't make up the votes" in the rest of the state, Madonna said.
If Bush can stay within range of Kerry in the Philadelphia area, his two keys for winning the state are holding down the Democratic advantage in Pittsburgh and surrounding blue-collar communities and expanding his margins in the state's center, which is largely rural.
Ohio
(20 electoral votes)
In an election focused so heavily on voter mobilization, John C. Green, a political scientist at the University of Akron, and Eric Rademacher, co-director of the Ohio Poll at the University of Cincinnati, plan to focus on how big an advantage each candidate can generate in his Ohio strongholds.
For Republicans, that's Hamilton County, which includes Cincinnati and its suburbs. In 2000, Bush carried the county by nearly 43,000 votes.
The Democratic bulwark is Cuyahoga County, which includes Cleveland and its suburbs. In 2000, Cuyahoga gave Gore a margin of just over 166,000 votes -- but that was down from Clinton's 178,000-vote advantage four years earlier.
