It’s now really almost over. 
 
 The hat trick of primaries in Wisconsin, Maryland and Washington, D.C., capped yet another no-drama evening in Mitt Romney’s march toward the GOP presidential nomination. Romney is now more than halfway toward the delegates he needs to win his party’s nod, and Rick Santorum lost his last shot at a big, momentum-changing Midwestern win. 
 
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 reset Romney takes three primaries Santorum speaks after loses 
 
 Below are POLITICO’s five takeaways on the night. 
 
 1) The curtain is closing 
 
 Santorum is vowing to fight on, with a defiant election night speech delivered in his home state of Pennsylvania, miles away from where the votes were cast, replete with Etch-a-Sketch references and other less than genial comments about Romney. He said the race is at “halftime,” even though most political watchers and Republican leaders think it’s in the fourth quarter. 
 
 He has a path to deny Romney 1,144 delegates — the number needed to win the GOP nod — if he stays in the game through May and June. And the primary may indeed last another month or two. But right now, there is now even less of a path to 1,144 for Santorum. 
 
 Romney was not poised for a blowout in Wisconsin, and Santorum can take some comfort from the margin there, having once again outperformed the final polls before the vote and the exit surveys. That speaks again to the fact that there is anti-Romney sentiment in the GOP, but the field has been too weak to take advantage of it. 
 
 (Also on POLITICO: PHOTOS: 50 craziest quotes of the 2012 race) 
 
 Romney was on track to amass at least 75 of the 98 delegates available on Tuesday night. 
 
 There is no real role for Santorum other than spoiler as exit polls showed him doing well among voters who had backed him before — the “very conservative” and evangelicals, who made up a smaller portion of the Maryland and Wisconsin electorate than in Southern states. 
 
 There is no real role for Santorum other than spoiler as exit polls showed Romney doing well among voters who had eluded him before — that is, the “very conservative” and evangelicals who made up a smaller portion of the Maryland and Wisconsin electorate than they did in Southern states. 
 
 Nonetheless, Romney made gains, and the narrative about him struggling with conservatives will continue, but it will become tougher to sell, even as concerns about the front-runner remain within the base. Santorum now is going to find it harder to get media oxygen and donor support. 
 
 “Since his wins in Alabama and Mississippi, Santorum has, essentially, had the two-man race he wanted, and he’s only won in one state, Louisiana,” said conservative strategist Keith Appell. “He can stay in as long as the money keeps coming in, but the delegate clock is ticking. No one can, or should, tell a candidate to get out of the race, and Santorum is also looking to the future.” 
 
 Appell added a note of caution regarding Santorum’s future, a theme that many have sounded in recent weeks. 
 
 “The Republican Party primary voters tend to be drawn to the so-called next person in line, and he could be that person if Romney wins the nomination but loses to Obama in the fall. If that’s part of his calculation, then he also has to consider how he conducts himself if he continues to lose and Romney looks more and more inevitable.” 
 
 It’s understandable that Santorum would want a chance to run in his home state later this month. But last night’s votes are likely to dent his poll numbers there. And the party has already started running out of patience. 

 Story highlights Evangelicals, tea partiers and others from Santorum's coalition voted for Romney 
 
 Santorum's campaign now pins its hopes on Pennsylvania and Texas 
 
 Big endorsements finally paid off for Romney campaign 
 
 Republican presidential frontrunner Mitt Romney had a big night Tuesday, sweeping primaries in the District of Columbia, Maryland and Wisconsin and putting more distance between himself and closest pursuer Rick Santorum in the race for delegates. 
 
 Here are five things we learned from Tuesday's vote: 
 
 Santorum's coalition fell apart 
 
 Wisconsin Republicans didn't just side with Mitt Romney on Tuesday -- they rejected Rick Santorum. 
 
 Make no mistake: Santorum campaigned hard in Wisconsin, raising the stakes for the primary. 
 
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 He ignored Maryland, the night's other big prize, and hit the Wisconsin bowling alley-and-cheese curd circuit, telling voters how a win there would shake up the GOP race. 
 
 "Wisconsin will send a sound around this country, like the sound of Lexington and Concord," Santorum said at a rally in Beaver Dam. "You will be the shot heard 'round the world." 
 
 That shot was never fired, because the Santorum coalition actually voted for Romney. 
 
 Big sweep for Romney 
 
 Evangelicals, tea party supporters, those supporting "traditional values" and people calling themselves "very conservative" went Romney's way, exit polls showed. 
 
 And one of Santorum's key messages -- that Romney can't stand up to Barack Obama because of his support for a health insurance mandate in Massachusetts -- also fell flat. 
 
 On the exit poll question of "Who do you trust to handle health care?" it was Romney who came out on top. 
 
 But Santorum will fight on 
 
 Over the last 10 days, the media and the Republican establishment seemed to come to a consensus -- cheered on by the Romney campaign -- that a Santorum loss in Wisconsin would spell doom for his campaign. 
 
 That may be true given Romney's wide delegate lead and his snowballing momentum, but Santorum showed no signs of quitting Tuesday, promising to forge ahead through May, when a slew of conservative Southern states will cast votes. 
 
 Santorum: "It's halftime" 
 
 He delivered his concession speech in the tiny town of Mars, Pennsylvania, boasting of his intimate connection with the state he represented in Congress for 16 years. 
 
 In an interview on CNN, Santorum's chief strategist John Brabender claimed that wins in Pennsylvania on April 24 and Texas on May 29 would propel his boss to the nomination over Romney -- a dubious claim considering that victories in both states would do little to cut into Romney's delegate advantage. 
 
 But even if a Pennsylvania win would somehow help secure the nomination for Santorum, the opposite is also true: A loss in his home state would cripple his campaign. 
 
 It's possible that might happen, and the Romney campaign knows it, which is precisely why the frontrunner will ride his latest burst of momentum into Pennsylvania on Wednesday for two days of campaigning on Santorum's turf. 
 
 Big-name endorsements finally had an impact 
 
 We've written in this space before that endorsements have been the fool's gold of this election cycle: attention-grabbing and sought after, but ultimately not worth very much. 
 
 This was not true in Wisconsin, Tuesday's marquee battleground. 
 
 Romney was practically swimming in big-name endorsements in the run-up to the vote, thanks to a GOP establishment increasingly eager to end the Republican-on-Republican mayhem and pivot to the fall election against President Barack Obama. 
 
 Top conservatives like Marco Rubio, Mike Lee and Wisconsin's own Paul Ryan jumped on the Romney train last week, as did former President George H.W. Bush. 
 
 And leading Republicans as ideologically distant as Mitch McConnell and Jim DeMint expressed their desire to see the Republican primary fight wrap up, implicitly siding with Romney. 
 
 Wisconsin was paying attention. 
 
 More than 60% of Republicans said the Romney endorsements were a factor in their votes, and 33% called them an "important" factor. Most of those voters, of course, broke heavily toward Romney. 
 
 The message these new surrogates were pushing -- that Romney is the likely nominee even if he doesn't have the delegates yet -- appeared to resonate. 
 
 A huge majority of Wisconsin Republicans, 83%, said Romney is "most likely" to win the GOP nomination. 
 
 Embattled governor has a posse 
 
 Exit polling out of Wisconsin revealed some bad news for Democrats and their organized labor allies: Republicans adore Scott Walker, their embattled governor who faces a recall election in June. 
 
 Walker's job is on the line thanks to his controversial push last year to roll back collective bargaining rights for state workers. 
 
 But the Republican base has his back. 
 
 According to exit polls, 82% of those who voted in Tuesday's primary approve of Walker as governor, and 71% "strongly" approve. 
 
 That emphatic support will be crucial for Walker as he faces off against his probable Democratic opponent, former Milwaukee mayor Tom Barrett, in a race likely to be decided by a tiny slice of undecided voters. 
 
 A poll from NBC News and Marist released last week showed that Wisconsin registered voters are evenly divided on Walker, with 48% percent approving of his job performance and 48% disapproving. 
 
 Only 6% of Wisconsinites in the poll said they were undecided about which candidate to get behind. 
 
 The formula for Walker, then, is pretty straightforward: sway most of the undecided voters, and get those who "strongly" approve of his record to the polls on June 5. 
 
 Barack Obama will be the Democratic nominee 
 
 OK, we already knew that. 
 
 But according to CNN's delegate estimate, the president collected enough delegates in Maryland and the District of Columbia on Tuesday night to formally secure the Democratic nomination. 
 
 Now we know for certain that Obama will accept his party's nomination at the Democratic National Convention in Charlotte. 
 
 The news officially puts to rest the silly chatter about a Democratic primary challenger (Howard Dean! Russ Feingold!) that bubbled up in 2010 during the most dismal moments of Obama's presidency.
– Mitt Romney scored a hat trick, winning all three of yesterday's primaries in Wisconsin, Maryland, and the District of Columbia. CNN and Politico each offer five takeaways: Wisconsin rejected Rick Santorum: It was Santorum's last shot at winning a Midwestern state, and he ignored Maryland in order to hit what CNN calls the "bowling alley-and-cheese curd circuit" in Wisconsin. It didn't work: His typical supporters, including evangelicals, tea partiers, and the "very conservative," voted for Romney anyway. Even so, he's not going anywhere: Despite the fact that many seemed to believe a Wisconsin loss would mean the end for Santorum, he's still focused on denying Romney the magic number of 1,144 delegates—and, for the time being, he still has a path to do so. All eyes are on Pennsylvania: Both Romney and Santorum have set the bar high for the April 24 primary in Santorum's home state. Romney knows that a loss in Pennsylvania could really spell doom for Santorum, so he's in the state today for two days of campaigning. Polls are tight, and some Romney supporters hope that Santorum will ultimately leave the race ahead of the primary if he thinks he won't win. Endorsements are starting to make a difference: Romney's VIP supporters may have offered less-than-enthusiastic endorsements, but exit polls in Wisconsin show that more than 60% of Republicans—most of them Romney voters—were influenced by those endorsements. Things are looking good for Scott Walker and Barack Obama: Wisconsin exit polls show that the governor has a lot of support as he faces a recall election in June. Meanwhile, in Maryland and DC, Obama scored enough delegates to secure the Democratic nomination. Click to hear from all the pundits who declared that it's over and Romney's the nominee after last night.