By Reid Wilson

By Wednesday morning, we will know whether Barack Obama or John McCain have earned the title of president-elect. In fact, we may know the answer by a relatively early hour on Tuesday. But beyond the banner headlines that will splash across every newspaper in America, other, less high-profile races will determine the direction the country takes.

From coast to coast, voters will cast ballots in 15 key races that will provide clues to the rest of the night to come, direct the first term of a new administration and indicate the next chapter in American politics. After absorbing the presidential news, keep an eye on these top contests:

Indiana: The first battleground state will also serve as a key, and early, indicator of Barack Obama’s success at turning out both the African American vote and younger voters. Polls in most of the state close at 6 p.m. Eastern, while polls in the Democratic stronghold of Lake County are in the Central Time Zone. That means the first numbers released at 7 p.m. will be the highest percentage John McCain sees in the state. Whether he holds on as Obama chips away at the Republican lead could determine if a big Obama landslide is in the offing. The early poll close doesn’t guarantee anything, though; during the Democratic primary, Lake County took hours to report any results.

Pennsylvania: No path to 270 electoral votes that doesn’t include Pennsylvania exists for John McCain. If he can peel classic Reagan Democrats out of Obama’s coalition, he has a chance to pull a major upset. Wondering why McCain is spending so much time on the state when other Democratic targets looked more promising earlier this year? Pennsylvania has no early voting, which means their electorate will be susceptible to persuasion until the last possible moment.

Nevada: Obama is likely to win the Silver State, and perhaps not by a small margin. But the reason he will win — a much-improved performance among Hispanic voters than John Kerry’s 2004 performance — could indicate a seismic shift in American politics. After divisive Republican rhetoric on immigration, even the most pro-immigration candidate in the GOP couldn’t keep Hispanic voters in the fold. That bodes ill for Republicans, leaving the party on the brink of damaging the relationship with Hispanic voters for good while having failed to deliver for their base.

Minnesota Senate: The most expensive, most-watched Senate race in the country is a true tossup, thanks to late accusations that a Texas businessman funneled thousands of dollars to Senator Norm Coleman, an accusation he vehemently denies. Independence Party candidate Dean Barkley gives voters uncomfortable with both Coleman and Democrat Al Franken a place to call home, meaning 43% may be enough to win. If he makes it to the Senate, some Democrats are worried that Franken could become a bomb-thrower.

Georgia Senate: If Obama’s coattails are going to cause any surprises, ex-State Rep. Jim Martin would be the most dramatic. Early voters are turning out in record numbers, waiting as many as eight or ten hours in line, and African Americans are showing up in historic numbers. Senator Saxby Chambliss’ vote for the emergency bailout legislation made the race close, but the new voters Obama turns out could push Martin over the line. Watch for this race to go to a runoff, to be held in early December.

Kentucky Senate: In a year of change, perhaps no one embodies Washington more than Senate Republican leader Mitch McConnell. But McConnell is making a smart argument, and Bluegrass voters will have a choice between a Democrat who offers generic change and a Republican who has delivered for his state. The election will be a referendum on McConnell and will have little to do with Democratic businessman Bruce Lunsford. Adding to the tension, Democrats would love to hang McConnell’s scalp on the wall as retribution for Tom Daschle’s loss in 2004.

Kentucky 02: An early canary in the coalmine could indicate Republicans should put away the champagne and reach for something stronger. Rep. Ron Lewis’ open seat, which includes Owensboro and Bowling Green and reaches north to the Louisville suburbs, is the site of a heated battle between Democratic State Senator David Boswell and Republican State Senator Brett Guthrie. Democrats started spending in the district late, but they’ve spent more than $1 million in October alone and almost four times what Republicans spent with a late investment. Guthrie looks like the early leader, but if Boswell declares victory early, a distinct possibility, it’s going to be a long and painful night for the GOP.

Washington 08: One of the last races to close, Rep. Dave Reichert’s career is once again in jeopardy, though if he loses his suburban Eighth District it won’t be his fault. Reichert has stellar constituent communications and voter contact operations, and the former King County sheriff is a good fit in the ultimate soccer mom district. But Democrats won the district in both the last two presidential elections, and Democratic statewide candidates have won the district by increasing margins. Democrat Darcy Burner isn’t a bad candidate, but if she wins this year, it will be because voters can’t see past the “R” after Reichert’s name.

Pennsylvania 12: If Rep. John Murtha loses his district, it will certainly be his fault. Voters in southwest Pennsylvania may elect to boot the seventeen-term incumbent in favor of a Republican after Murtha called his constituents “racist,” then attempted to apologize by calling them “rednecks.” Like the Kentucky Senate race, this contest will be decided by voter feelings about the incumbent, not about GOP businessman William Russell. Murtha will dramatically outspend Russell (Don’t be fooled by Russell’s good fundraising; much of his money was raised through the mail, a distinctly expensive way to pick up cash), but both parties are advertising as Republicans smell a rare pickup opportunity.

Wisconsin 08: Another Democrat who got himself in trouble will face off against a talented Republican challenger when Rep. Steve Kagen and former Assembly Speaker John Gard face each other for a second straight election. Kagen has talked himself into a corner while Gard has made a lot of right moves. It’s also one of a few districts in which the DCCC and the NRCC are spending at relative parity. If Kagen keeps his seat, Democrats can breathe easy about most incumbents who first won in 2006. If Gard prevails, Democrats may have territory to give back.

New Mexico 01: Sometimes a wave sweeps away even the most qualified candidates. Bernalillo County Sheriff Darren White is one of the best candidates in the country, and he’s running against a flawed, but not disastrous, Democratic candidate in Albuquerque. Heather Wilson held the seat even as it moved increasingly left, but even she would have trouble in this environment. Democratic groups led by the DCCC have outspend Republican groups more than five to one, and although White is a good candidate, Democrat Martin Heinrich is likely to head to Congress in January.

Washington, North Carolina Governor: In the two most competitive governor’s mansion contests this year, Republicans have successfully appropriated the “change” message that is hurting their party so much elsewhere. Dino Rossi, the Republican who lost to Democratic Governor Chris Gregoire in Washington by 129 votes in 2004, still refers to the multiple recounts it took to settle that election, and many voters feel the same way, making Washingtonians prime candidates for ticket-splitting. Charlotte Mayor Pat McCrory and his allies have labeled their Democratic opponent Status Quo Bev Perdue, and for North Carolina voters change could mean electing their first GOP governor since 1988.

California Proposition 8: Three states have legalized same-sex marriage through court rulings, but California is going to be the first state to vote on whether to ratify, or overturn, that decision. The last two independent polls show voters narrowly rejecting the same-sex marriage ban, which would make California just the second state — after Arizona — to defeat such a ban. Supporters of a ban are trying again in the Copper State and for a first time in Florida, but gay marriage proponents have the best-funded campaign, and the best chance to send a message that a one-time wedge issue is could be losing power.

New York State Senate: Democrats are just two votes away from a majority in the Empire State’s upper chamber, meaning they need to flip just one seat in order to be in complete control of state government for the first time since the 1964 elections. If they do, Democrats will have sole control over redistricting before the 2012 cycle, giving the party the ability to determine which members of Congress are drawn out of their districts when the state loses two seats in reapportionment. National Democrats have made redistricting a priority, and New York is on the front lines of their fight.

Reid Wilson is an associate editor and writer for RealClearPolitics. He can be reached at [email protected]