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Pablo Martinez Monsivais, Associated Press
President Barack Obama, center, during a campaign event for U.S. Senate candidate Gary Peters, right, and gubernatorial candidate Mark Schauer, left, at Wayne State University, Saturday, Nov. 1, 2014 in Detroit, Mich.

LANSING, Mich. — Candidates and their allies are frantically working to get their supporters to vote in the final days before Tuesday's midterm election brings what could be the closest Michigan governor's race in a quarter-century and a new U.S. senator.

Which side does a better job turning out the base and persuading voters, particularly in the "low-propensity" category, may influence not only close top-of-the-ticket races but also contests that will shape whose party controls the Legislature, attorney general and other offices.

Republican Gov. Rick Snyder and GOP Senate candidate Terri Lynn Land on Sunday were continuing in parts of a three-day, 17-city bus tour with GOP candidates. Snyder planned to campaign in Traverse City, Gaylord, Mount Pleasant and Midland.

Democratic challenger Mark Schauer was on a five-day, 19-city tour with Sunday stops in Detroit, Saginaw, Jackson and East Lansing. Democratic Senate candidate Gary Peters was expected in Flint and the Detroit area.

The stretch run is a frenzied pace of crisscrossing the state, knocking on doors, making calls, ensuring absentee ballots are returned and hoping the weather is nice on Election Day. But it's also the culmination of voter targeting, new technologies and other strategies methodically fashioned and implemented by the state's major political parties for two years.

After watching President Barack Obama defeat Mitt Romney by 9 percentage points in 2012 without even campaigning in the state, GOP leaders decided that the party needed to be in more regular contact with voters instead of just in the last months before an election. It established permanent, full-time regional field offices and launched its "MI Team Dashboard" — a new Internet-based program enabling activists to help identify neighbors, Facebook friends, their political leanings and tendency to vote.

"It exponentially expands our reach," said Republican Party Chairman Bobby Schostak, whose party has made 4 million voter contacts this year.

His Democratic counterpart, Lon Johnson, is focused on contacting nearly 1 million Democrats believed to have voted in recent presidential elections but not in the 2010 midterm contest, when Republican Rick Snyder trounced Democrat Virg Bernero to become governor. The 43 percent of the voting-age population who cast 3.2 million ballots four years ago was the lowest since 1990.

Higher overall turnout is good for Democrats. Voting expert Mark Grebner has estimated that if 3 million votes are cast, they traditionally are split evenly. But for each additional million ballots, Democrats get a 100,000-vote edge.

Democrats insist they can boost turnout by using Obama's state-of-the-art voter database to find and motivate 200,000 Democrats who voted for the president, especially by pushing them to vote early with an absentee ballot. The party also launched a program that lets voters apply online for absentee ballots.

Citing an uptick in absentee ballot requests and the close gubernatorial race, Detroit's city clerk estimates about 40 percent of the city's 529,000 registered voters will cast ballots, up from 31 percent turnout the last time Michigan elected a governor.

Weather also affects turnouts, and the National Weather Service said there's a 50-50 chance of rain Tuesday in metropolitan Detroit and mid-Michigan, with rain likely in the western Lower Peninsula. Temperatures statewide should range from the 40s to about 60.

Matt Marsden, whose Pontiac-based political firm RevSix helps Republican candidates "micro target" voters by tracking absentee ballots, said it appears Democrats are indeed convincing more people who don't automatically receive an absentee ballot every election to request one.

"Here is a pool of people that you know you can reach," Marsden said.

About 835,000 absentee ballot requests had been made as of Thursday, up from 794,000 in 2010, with more expected in the closing days.

Marsden questioned whether the absentee ballot drive alone could swing the governor's race but said it could sway legislative races where Democrats are trying to wrest control from the GOP.

Outside groups like Working America, an affiliate of the AFL-CIO, are knocking on doors in the Detroit area to try to cut into Snyder's edge with working-age men, said political director Matt Morrison. The Michigan League of Conservation Voters has a ground game to help Schauer and Peters, and the conservative Americans for Prosperity is knocking on doors and making calls, too.

Schostak said he isn't concerned about Democrats' tactics, saying three times as many Republican-leaning low-propensity voters have absentee ballots than in 2010.

"We've made all of the message clear for a long time now about this governor, this administration, the things we've accomplished the last four years and why he's earned another four years," he said.

But Johnson said 30 percent more Democrats will vote absentee this year than in 2010. Snyder's critics hope anger — from people upset about the elimination or reduction of tax exemptions, 2011 education funding cuts and a new right-to-work law — is a galvanizing force.

"We have to close the deal on Election Day," Johnson said.

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