The Note's Must-Reads are a round-up of today's political headlines and stories from ABC News and the top U.S. newspapers. Posted Monday through Friday right here at www.abcnews.com

Compiled by ABC News' Jayce Henderson and Ben Waldron

PRESIDENT OBAMA AND VICE PRESIDENT BIDEN: The New York Times' Mark Leibovich: " For a Blunt, an Uneasy Supporting Role" As President Obama reviewed the comedy routine he was to deliver at the recent White House Correspondents' Association dinner, one joke struck him as too hot. It suggested he might dump Vice President Joseph R. Biden Jr. from the ticket. LINK

The Washington Post's Peter Wallsten and Dan Eggen: " Biden comments on same-sex marriage expose internal White House Divisions" When asked about his views on same-sex marriage, Vice President Biden said he is "absolutely comfortable" with men marrying men and women marrying women. When Education Secretary Arne Duncan was asked Monday whether he thinks that same-sex couples should be able to marry, he said, "Yes, I do." LINK

The Hill's Amie Parness: " Obama not comfortable on gay marriage" The White House and the Obama campaign on Monday sought to contain pressure on President Obama to change his stance on gay marriage following Vice President Biden's remark that he's "absolutely comfortable" with it. Obama has said that he is opposed to gay marriage while adding the caveat that his views are "evolving" - a carefully phrased position that has angered some gay-rights activists and donors. LINK

Politico's Joseph Williams: " Big Labor fails in line with Obama reelection campaign." Organized labor's rumblings about sitting out President Barack Obama's reelection have turned out to be an empty threat. The Teamsters' Monday endorsement makes it the latest major union to fall in line behind the president's campaign, joining the Service Employees International Union, the AFL-CIO and many other labor heavyweights. LINK

MITT ROMNEY: ABC News and Yahoo News' Chris Moody: " Romney VP speculation fills the weekend with Jeb Bush, Rubio, Ayotte and Gingrich weighing in" Although there are several months left before Mitt Romney's expected announcement of a running mate, the weekend was filled with speculation about his choice. LINK

The Washington Times' Seth McLaughlin: " Romney wins Santorum endorsement" Former Pennsylvania Sen. Rick Santorum endorsed Mitt Romney for president Monday night in an email to supporters, assuring them that he's convinced the former Massachusetts governor with fight for the issues important to social conservatives, tea party members and working families. LINK

The LA Times' Seema Mehta: " Mitt Romney campaign has awkward moments in Ohio." Mitt Romney's campaign events tend to be picture-perfect and planned with such attention to detail that a late start might be considered a failure. By that measure, Monday was a rare day when the campaign went off-track. A backer introduced Romney by slamming President Obama for taking credit for the killing of Osama bin Laden, comparing Obama to Ronald McDonald. And when a woman said Obama should be tried for treason, Romney didn't disagree and asked the woman to follow up her question. LINK

Bloomberg's John McCormick and Richard Rubin: " Romney Asked About His Foreign Tax Credits at Ohio Campaign Stop" Mitt Romney, who claimed a foreign tax credit on his 2010 federal returns, said he doesn't think he pays any foreign income taxes when asked about the matter by a man at a campaign stop in Ohio. LINK

OHIO / OTHER: USA Today's Martha Moore: " Columbus, Ohio, hit with barrage of political ads" Presidential primaries can be counted on to bring flash floods of political advertising to one state after another: brief, intense and noisy. As the amount of money spent on political persuasion has risen, there are now some places where political ads are more like a steady rain. Here in Columbus, it is pouring. LINK

The Wall Street Journal's Amy Schatz: " Campaign Text-Donation Plan Gets a New Push" Political campaigns are already raising millions of dollars via the Internet. Now, two political consulting firms are pushing a bipartisan plan to make online giving even easier by letting cellphone users make small donations with a single text. LINK

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