GREAT FALLS – Democratic U.S. Sen. Jon Tester, who won a hard-fought, close contest Tuesday over Republican challenger U.S. Rep. Denny Rehberg, said Wednesday it’s time for Congress to put aside partisanship and tackle the nation’s pressing problems. 
 
 Tester, speaking in Great Falls shortly after he was declared the winner, said those problems include the federal deficit, taxes, the economy – and the tidal wave of “relentless, secretive political spending” seen in his race and many others across the nation. 
 
 “This is larger than me,” he said in an interview. “The outside money that’s coming in (to politics) is bad for democracy. 
 
 “We’ve got to get some transparency in this process, at a minimum ... so we know who’s footing the bill. It shouldn’t be about someone who has a ton of money, trying to buy an election.” 
 
 Tester, 56, a farmer from Big Sandy, led by 16,000 votes over Rehberg late Wednesday, with some votes yet to be counted in Yellowstone, Silver Bow, Ravalli and Flathead counties. 
 
 Tester had 48.5 percent of the vote, while Rehberg had nearly 45 percent. Libertarian Dan Cox of Hamilton carried a significant 6.5 percent, one of the highest showings by a Libertarian in a statewide race. 
 
 Rehberg, 57, Montana’s sole congressman since 2001, conceded the race Wednesday morning, issuing a statement that said it had been “an honor to serve the people of Montana.” 
 
 “The voters of our state have spoken and I respect their decision,” he said. “Senator Tester and I share an abiding love for Montana and America, a value which transcends political party or disagreements on matters of policy.” 
 
 Tester also complimented Rehberg on a “well-fought race,” and said he knew Rehberg would agree that the nation faces big challenges that need to be addressed. 
 
 “Despite our differences, we belong to the greatest state and the greatest nation in the world,” Tester said. “We owe thanks to Congressman Rehberg. He has spent a career in public service.” 
 
 Rehberg, a rancher from Billings, has been a key figure in Montana politics for more than 30 years, also holding office as state representative and lieutenant governor. 
 
 Tester said he’s hopeful Congress will start acting on plans to reduce the nation’s debt and federal deficit and reform the tax code, to make it simpler and more fair. 
 
 “I think there is a nucleus of people back in (Washington) D.C. who are willing to do it,” he said. “The bottom line is ... when we deal with that in a common-sense way, I think it will help the economy.” 
 
 Tester also said he’d like his wilderness/jobs bill to pass Congress, either as part of an Interior spending package this year or as a stand-alone bill next year. The measure, stalled in Congress since 2009, would create new wilderness in western Montana forests while identifying new acreage for logging. 
 
 Yet Tester spoke most forcefully Wednesday about shining a light on the river of money spent on his contest and many others by so-called outside and “dark” money – groups that often don’t have to disclose or detail their donors or expenditures. 
 
 Observers estimated that outside groups spent $30 million or more on the Tester-Rehberg matchup, including at least half that amount by nonprofit groups that can keep their donors secret. 
 
 The contest was the most expensive in Montana history, as Rehberg and Tester spent about $20 million of their own campaign money, in addition to the outside cash by party and interest groups. 
 
 Tester said groups should fully disclose their spending to influence federal elections – including the nonprofits that now keep their donors secret. 
 
 On Tuesday, Tester sprinted to a solid lead of about 20,000 votes in early returns and never relinquished it. Cox also started out strongly, polling 5 percent to 6 percent in the first returns – a level he held throughout the vote-counting. 
 
 While the Associated Press called the race at about 9 a.m. Wednesday, elections officials in Billings, Kalispell, Butte and Hamilton were still counting some ballots late Wednesday afternoon. 
 
 The biggest lag occurred in Billings, where officials said the final count wouldn’t be finished until Wednesday evening. Problems with vote-counting machines and late voting by Election Day registrants delayed the count in Yellowstone County. 
 
 Missoulian State Bureau reporter Mike Dennison can be reached at 1-800-525-4920 or at mike.dennison@lee.net. ||||| Democratic candidate Heidi Heitkamp has won the U.S. Senate race in North Dakota, defeating favored Republican congressman Rick Berg. 
 
 Democrat Elizabeth Warren, center, waves to the crowd with her husband Bruce Mann, left, during an election night rally at the Fairmont Copley Plaza hotel in Boston after Warren defeated incumbent GOP... (Associated Press) 
 
 Flanked by family members, Sen. Claire McCaskill, D-Mo., looks up as she talks about her mother, Betty Anne McCaskill, who recently passed away, while declaring victory over challenger Rep. Todd Akin,... (Associated Press) 
 
 U.S. Rep. Tammy Baldwin, D-Wis., waves to supporters after making her a victory speech in Wisconsin's U.S. Senate race, Tuesday, Nov. 6, 2012, in Madison, Wis. Baldwin defeated former Wisconsin Gov. Tommy... (Associated Press) 
 
 Berg had been expected to win the race, and Republicans had counted on his victory in their failed attempt to take control of the Senate. 
 
 Heitkamp won the race by fewer than 3,000 votes, and Berg could have asked for a recount. 
 
 He conceded the race Wednesday with a qualifier: He was stepping aside barring any unforeseen circumstances with the state canvasing board that certifies the race results. 
 
 That canvasing process is to begin Friday. It will account for late-arriving absentee ballots that were postmarked in time to be counted in the election. ||||| Democrats on Wednesday strengthened their control of the U.S. Senate by pulling off an upset win in the conservative state of North Dakota, a final blow to Republicans who had once been favored to take control of the chamber. 
 
 Democratic candidate for North Dakota's U.S. Senate seat, Heidi Heitkamp, holds up the Oct. 20, 2012, Fargo Forum, Wednesday morning Nov. 7, 2012, in Bismarck, N.D. The October newspaper had Berg leading... (Associated Press) 
 
 Democrat Elizabeth Warren, center, waves to the crowd with her husband Bruce Mann, left, during an election night rally at the Fairmont Copley Plaza hotel in Boston after Warren defeated incumbent GOP... (Associated Press) 
 
 Flanked by family members, Sen. Claire McCaskill, D-Mo., looks up as she talks about her mother, Betty Anne McCaskill, who recently passed away, while declaring victory over challenger Rep. Todd Akin,... (Associated Press) 
 
 U.S. Rep. Tammy Baldwin, D-Wis., waves to supporters after making her a victory speech in Wisconsin's U.S. Senate race, Tuesday, Nov. 6, 2012, in Madison, Wis. Baldwin defeated former Wisconsin Gov. Tommy... (Associated Press) 
 
 The North Dakota race was the last to be called of Tuesday's 33 Senate contests. With it, Democrats increased their advantage in the chamber by two, to 55-45, counting two independents expected to align with them. 
 
 But newly re-elected President Barack Obama must still contend with a divided Congress _ and the potential for more political gridlock _ since Republicans kept their solid majority in the House of Representatives. 
 
 The numbers in both chambers were largely unchanged after Tuesday's vote. But the new Congress will be more diverse, with a record 20 women winning Senate seats, including two Democrats who will be the first openly gay senator and the first female Asian-American senator. A record number of Latinos will serve in the House. 
 
 Democrats prevailed in two close races in conservative western states. In North Dakota, former state attorney general Heidi Heitkamp won a surprise victory over a heavily favored Republican congressman in a bid for a seat being vacated by a retiring Democrat. In Montana, Sen. Jon Tester, who narrowly won his seat when Democrats captured the Senate in 2006, was re-elected. 
 
 Republicans hurt their chances of winning the Senate when candidates in Missouri and Indiana _ both states won by Republican presidential nominee Mitt Romney _ made damaging comments about rape and abortion and went on to lose. An incumbent Republican fell in liberal Massachusetts, while Republicans also lost a seat in Maine. 
 
 Only a dozen or so Senate races out of the 33 on the ballot had been seen as competitive. Throughout Tuesday night and into Wednesday, one after another was won by Democrats. Republicans, though, picked up a Democratic-held seat in Nebraska and fended off strong challengers in Nevada and Arizona. 
 
 Control of the Senate virtually ensures that Obama's signature legislative achievement, his health care overhaul, will be fully implemented in 2014. Republicans had promised to repeal it. 
 
 More than $2 billion was spent on the nasty fight for Congress. All 435 House seats were on the ballot, and Republicans retained control there, though Democrats made a few gains. With most races decided, the new House looked like it would resemble the current one, which Republicans control by 240-190, with five vacancies. 
 
 While Republican Rep. Paul Ryan lost the vice presidency, he did win another term to his Wisconsin House seat. 
 
 House Speaker John Boehner, who gets to keep his job, offered to work with both parties in Congress. But Boehner also said that by keeping Republicans in control of the House, voters made clear there is no mandate for raising taxes. Obama has proposed ending Bush-era tax cuts for households earning over $250,000 a year. 
 
 The first post-election test of wills could start next week, when Congress returns from its election recess to deal with unfinished business _ including the looming so-called fiscal cliff of $800 billion in tax increases and automatic spending cuts to take effect in January if Congress doesn't come up with a compromise to head them off. Economists warn that failure to reach a deal could plunge the U.S. back into a recession. 
 
 Newly elected Elizabeth Warren, a Massachusetts Democrat who won a marquee race against incumbent Scott Brown, said Wednesday she believes there is a "lot of room for compromise." Warren, a favorite among liberals as a leading consumer advocate, told NBC's "Today" that Congress can find a middle ground to bring down the deficit by cutting spending while raising revenues. 
 
 Democrats began the year in a precarious position, defending 23 Senate seats and losing several retiring veterans in Republican-leaning states, all while voter discontent lingered over the sluggish economy and Obama's health care overhaul. But the Democrats fielded some strong candidates, and Republican prospects were undermined by some candidates who apparently proved to be too conservative and by the surprise retirement of Sen. Olympia Snowe in Maine. Independent Angus King, a former governor, won a three-way race to replace her. 
 
 King has vowed to be a bridge between the parties and has not said whether he would caucus with the Democrats or Republicans. However, he was expected to side with the Democrats after Republican groups spent hundreds of thousands of dollars on ads attacking him. 
 
 Senators who rode the Democratic wave in 2006 were elected to second terms in Ohio and Pennsylvania. In Virginia, Tim Kaine, a former governor and Democratic national party chairman, won a costly, close race. 
 
 In Connecticut, a Democrat won a seat that Republicans had once hoped would be captured by Linda McMahon, the former head of World Wrestling Entertainment who spent more than $42 million of her own fortune in the race. 
 
 Women made big gains in the Senate. Democratic congresswoman Tammy Baldwin won in Wisconsin and will become the first openly gay senator. Democratic congresswoman Mazie Hirono of Hawaii becomes the first Asian-American woman to serve in the Senate. 
 
 In New Hampshire, wins by two Democrats in House races gives the state, which has two women senators, an all-female delegation to Congress, along with a newly elected woman as governor. 
 
 Congress almost got its first black Republican woman, but Mia Love lost a close House in Utah. 
 
 A record number of Latin-American congressional candidates ran, according to the National Association for Latino Elected and Appointed Officials, and the House will have several new Latino members. 
 
 Republican Ted Cruz, the son of a Cuban-born father and a tea party darling, won a Senate race in Texas. Republican Deb Fischer, another tea party favorite, won in Nebraska. 
 
 Republicans also did well in the Southwest. Arizona congressman Jeff Flake won a tough race to hold a Republican seat and Nevada Republican Sen. Dean Heller turned back a strong challenge. 
 
 While Democrats will increase their margin in the Senate, they will remain below the 60-vote supermajority needed to easily pass legislation under Senate rules. 
 
 Senate Minority Leader Mitch McConnell offered to work with the Democrats and Obama if the president is ready to compromise. 
 
 "To the extent he wants to move to the political center, which is where the work gets done in a divided government, we'll be there to meet him half way," McConnell said. 
 
 ___ 
 
 Associated Press writers Donna Cassata contributed to this report from Washington.
– The fat lady may have sung on the presidential race last night, but results are still trickling in from some of the country's closest races. So far, everything's coming up blue; Democrats have extended their Senate majority to 53, not counting the two independents expected to poll with them, after winning a pair of nail biters. In North Dakota, former Attorney General Heidi Heitkamp has scored what Politico terms an "upset" win over Rep. Rick Berg to claim the last unsettled Senate seat of the election. Heitkamp won with fewer than 3,000 votes, the AP reports, a margin so small that Berg could have demanded a recount, but he instead conceded late this afternoon. Earlier, Democrat Sen. Jon Tester won an excruciatingly close re-election battle over Rep. Denny Rehberg, after a bitter campaign that dominated Montana politics for two years, the Missoulian reports. Tester likely benefited from a strong performance by Libertarian Dan Cox, who managed 6% of the vote—most of it likely at Rehberg's expense.