By Glen Johnson, Globe Staff

First lady Michelle Obama is coming back to Boston next month on a fund-raising mission for her husband’s reelection campaign. She will attend two events on March 9 at the Institute of Contemporary Art. The first, a reception, has tickets costing $500 and up. The second, a dinner, has tickets beginning at $5,000. Both events will benefit the Obama Victory Fund, a joint fund-raising committee supporting the president’s reelection committee, Obama for America, and the Democratic National Committee.

By Shira Schoenberg, Globe Correspondent

Republican presidential candidate Newt Gingrich previewed a new line of attack against former Massachusetts Governor Mitt Romney: hitting him on gun rights. In a new web site, romneyguns.com, Gingrich poked fun at Romney for his much-ridiculed 2008 comment that he hunts “small varmints.” The site features a graphic of a suit-wearing Romney holding a gun and wearing a hunting cap. The site charges that Romney supported the Brady Bill, which mandated federal background checks on gun buyers, raised fees for Massachusetts gun owners, and supported tough gun laws in Massachusetts.

By Shira Schoenberg, Globe Correspondent

With final results in from Tuesday’s caucuses and primary, former Pennsylvania Senator Rick Santorum pulled off large margins of victory in three non-binding nominating contests, all marked by low turnout. In Missouri, which held a primary but will not use the results to award delegates, Santorum got 55.2 percent of the vote. Former Massachusetts Governor Mitt Romney got 25.3 percent, and Texas Representative Ron Paul got 12.2 percent. Former House Speaker Newt Gingrich did not appear on the ballot. There were just under 252,000 votes cast, according to the Associated Press tally, less than half of the 588,000 votes that were cast in the Republican primary in 2008.

By Shira Schoenberg, Globe Correspondent

With former Pennsylvania Senator Rick Santorum scoring victories in all three non-binding nominating contests on Tuesday, the next question will be whether the candidate can boost his fundraising to match the organizations of his rivals. As of the end of 2011, Santorum was far behind his Republican rivals in the money chase. His campaign raised just $2.2 million in 2011. The pro-Santorum super PAC, the Red, White, and Blue Fund, raised just $764,000. In contrast, his GOP rival Mitt Romney raised $56.1 million and a pro-Romney super PAC raised $30.1 million.

By Shira Schoenberg, Globe Correspondent

A new poll has President Obama, a Democrat, pulling ahead of Republican candidate Mitt Romney in Virginia, a crucial swing state. The Quinnipiac University poll released today finds Romney, the former Massachusetts governor, would get 43 percent of the vote compared to 47 percent for Obama. In three previous Quinnipiac polls in Virginia, in September, October, and December, Romney edged out Obama in a head-to-head match-up. The poll shows women and independents are now backing the president over Romney.

By Noah Bierman, Globe Staff

US Senator Scott Brown, who hopes to garner reelection support from the state’s large Irish-American population, has become a central player in a battle to allow more Irish workers to come to America. Brown’s efforts to break a logjam in the Senate over a bill that would allow an additional 10,500 skilled Irish workers to gain work visas every year have attracted significant attention in the Irish press and are being watched closely by activists around the US.

By Shira Schoenberg, Globe Correspondent

Former Pennsylvania Senator Rick Santorum, fresh off his upset victories in three non-binding nominating contests, has immediately started attacking the Republican frontrunner, former Massachusetts Governor Mitt Romney. Speaking in a series of TV appearances this morning, Santorum referred to Romney as “Mr. Big Government.” On CNN, Santorum said Romney “was for government takeover of health care, was for government takeover of the private sector in the Wall Street bailout, and was for the government takeover of industry and energy with cap-and-trade.”

By Bobby Caina Calvan, Globe Staff

Rick Santorum catapulted back into the presidential limelight yesterday, soundly defeating front-runner Mitt Romney in the Minnesota and Colorado caucuses and the symbolic Missouri primary and casting doubt about the former Massachusetts governor’s ability to win over conservatives in the nation’s heartland. Time and again, Romney has tried to vanquish his competition and yesterday’s results was the latest sign that he faces challenges in establishing the broad base of support from his own party as the campaign moves closer to next month’s Super Tuesday.

By Glen Johnson, Globe Staff

Despite a three-state sweep last night, Rick Santorum gained exactly zero delegates to this summer’s Republican National Convention. What the former senator claimed was critical momentum in his party’s nominating contest, while Mitt Romney and Newt Gingrich earned a repudiation of the frontrunner status they each have held during the campaign. That is most troubling for Romney, whose trump card has been his claim of having the nationwide organization, financing, and institutional backing to compete in all 50 states.

By Bryan Bender, Globe Staff

Taking aim at an area of federal spending left unchecked for generations, two dozen lawmakers today plan to propose legislation mandating deep cuts in the US nuclear arsenal – including submarines, missiles, aircraft, and weapons design laboratories.

By Bobby Caina Calvan, Globe Staff

Mitt Romney is hoping to tamp down a resurgent Rick Santorum today, as Republicans in three states -- Colorado, Minnesota, and Missouri -- take center stage in a presidential contest brimming with political drama.

By Shira Schoenberg, Globe Correspondent

An investigative package of stories and graphics in the Washington Post today reported that three Massachusetts representatives -- John Olver, John Tierney, and Stephen Lynch -- requested earmarks for projects that were near their personal property or that benefited an organization employing a family member.

By Brian C. Mooney, Globe Staff

Today, Restore Our Future, the so-called super PAC supporting Romney’s presidential candidacy, amended its latest report to the Federal Election Commission, solving the mystery of a $250,000 contribution last August from a California limited liability company that appeared to exist only on paper. The donation from “Glenbrook LLC” of Redwood City was replaced with a pair of $125,000 donations from Jesse Rogers, a Palo Alto investment fund manager, and his wife, Melinda.

By Tracy Jan, Globe Staff

The Massachusetts delegation called upon their congressional colleagues this afternoon to support a permanent fix to a controversial Medicare formula that would cut payments to doctors by nearly 30 percent if left alone. A full repeal of the flawed formula, known as the sustainable growth rate, is particularly important to the Bay State economy, the delegation argues in a letter to Dave Camp, chairman of the House Committee on Ways and Means, and Max Baucus, chairman of the Senate Committee on Finance.

By Shira Schoenberg, Globe Correspondent

Tonight’s caucuses in Colorado and Minnesota and primary in Missouri are three examples of contests that have received attention from candidates and the press – but have little implication in the race for delegates. The spate of non-binding contests is the result of several factors, including the desire of states to vote early enough to be meaningful in the selection process, combined with rules that give states incentives to choose their nominees later on.

By Glen Johnson, Globe Staff

A third-party group that agreed last week to abide by Scott Brown and Elizabeth Warren’s ban on outside advertising in their much-anticipated US Senate race is today expanding its website focused on the Republican incumbent’s record. It is the first effort by an outside group to take advantage of gaps in an agreement that both candidates hailed as revolutionary when they signed the so-called “People’s Pledge.” Yet it is silent on information posted on a website.

By Shira Schoenberg, Globe Correspondent

James Bopp, a conservative attorney who has led the opposition to campaign finance laws, today endorsed Republican presidential candidate Mitt Romney. Romney has been a major beneficiary of laws Bopp has advocated for. Bopp’s most well-known victory was in the 2010 Supreme Court case Citizens United, which struck down long-standing campaign finance laws by allowing corporations, non-profits, and unions to contribute unlimited amounts of money to political causes and candidates. Bopp was the original lawyer representing the conservative non-profit Citizens United.

By Tracy Jan, Globe Staff

Massachusetts Congressman Edward Markey applauded the Obama administration’s announcement this morning that it would pledge $156 million for Alzheimer’s research and care, a progressive, irreversible brain disorder afflicting approximately 5.1 million Americans.

By Shira Schoenberg, Globe Correspondent

President Obama is putting a renewed focus on raising money through his super political action committee, after fundraising figures showed the Democratic president falling far behind his Republican rivals in super PAC fundraising. Obama campaign manager Jim Messina wrote on the Obama campaign blog that Obama dislikes the current campaign financing system, but Democrats cannot play by two sets of rules.

By Bobby Caina Calvan , Globe Staff

There’s little doubt Mitt Romney will be victorious today in Colorado’s GOP caucuses, but less certain is whether he can count on this state in November should he prevail as his party’s nominee. Republicans insist that Colorado’s conservative values remain as solid as the Rocky Mountains, but a string of high-profile losses against Democrats raise doubts about the party’s ability to put up a fight against the Obama campaign in what’s supposed to be a crucial battleground state.