Do you subscribe to Read In? Sign up here and get D.C.'s best morning tip sheet in your inbox every day.

A1: The stories you need to read before your first conference call.

-- The Supreme Court ruled Monday that legislative bodies such as town councils can begin their meetings with prayer, even if it overtly favors a specific religion. The 5 to 4 ruling held that Christian prayers before meetings in Greece, N.Y., did not violate the Constitution. Justice Anthony Kennedy wrote the opinion along with the Court's four conservative justices. (Washington Post)

-- Massachusetts will scrap its dysfunctional health insurance website after deeming it too costly and time-consuming to fix. The commonwealth will join the insurance marketplace, at a cost of about $100 million, while it installs new software. That software, built by Virginia-based hCentive, has been used in successful exchanges in Colorado, Kentucky and New York. (Boston Globe)

-- Thirty pro-Russian separatists and four Ukrainian government troops have been killed during operations aimed at dislodging the separatists from Slovyansk, a city of 125,000 in the country's restive east, Ukraine's interior minister said today. International flights into and out of Donetsk were suspended on Tuesday. (Associated Press)

-- Sens. Bill Nelson (D-Fla.), Chris Coons (D-Del.) and Tim Johnson (D-S.D.), all of whom voted for a non-binding resolution urging the construction of the Keystone XL pipeline, now say they will vote against an amendment sponsored by Sen. John Hoeven (R-N.D.) allowing construction of the pipeline. That leaves Hoeven at least one vote short of the 60 votes needed to advance the bill. (CNN) Paul Kane cautions: There's no guarantee the Hoeven amendment even comes to a vote, if Democrats and Republicans don't agree on amendment procedures during debate on the Shaheen-Portman energy bill.

-- House GOP leaders are making a point to teach members first elected in the Tea Party waves of 2010 and 2012 the appropriations process. The House began voting on appropriations bills last week, their earliest start since 1974; the Senate is expected to begin later this month. The bills have no spending earmarks, but they do include policy earmarks. Chief deputy whip Peter Roskam (R-Ill.) is encouraging younger members to participate in the process. (Washington Post)

-- Ed O'Keefe empties his notebook: House Appropriations Committee chairman Hal Rogers (R-Ky.) explained the process at a weekly House GOP conference meeting in February. He and several subcommittee chairmen, including Rep. Ander Crenshaw (R-Fla.), made subsequent pitches in March and April. Members use an internal computer database to submit appropriations requests in pdf format, though aides declined to say how much the database cost.

-- The flow of pure heroin into the U.S. will intensify after the U.S. pulls troops out of Afghanistan by year's end, FBI Director James Comey said Monday in Tampa. He also said he was worried about foreign fighters in Syria making connections that could lead "to a future 9/11." (Tampa Tribune)

-- Front Pages: WaPo, NYT and L.A. Times all lead with the Supreme Court's prayer decision. WSJ leads with negotiations between prosecutors and Credit Suisse that could yield the biggest tax settlement in U.S. history. And USA Today fronts Attorney General Eric Holder's warnings that banks could face future prosecution.

National Roundup: What's happening outside the Beltway.

-- WH'16: Vice President Biden will headline a fundraiser for the South Carolina Democratic Party on Friday at the Capital City Club before addressing USC's commencement ceremony. It's Biden's second big fundraiser for the South Carolina Democrats; he headlined their Jefferson-Jackson Dinner last year. (The State)

-- North Carolina: Sen. Kay Hagan (D) has sent mailers to Republican primary voters accusing state House Speaker Thom Tillis (R) of backing ObamaCare. Tillis shot back, charging Hagan with "meddling" in the GOP primary. (Washington Post, CNN) Tillis's vote total is the number to watch tonight: If he can't reach 40 percent of the vote, he'll be forced into a mid-July runoff. And that would cost Tillis and his GOP allies a ton of money that could otherwise be spent on Hagan.

-- Nebraska: Bank president Sid Dinsdale (R) has lent his campaign $1 million since late March, and now he's spending that money on television. ( Dinsdale has purchased $159,000 in last-minute ads in advance of next week's primary. The three leading candidates -- Dinsdale, state Treasurer Shane Osborn (R) and former Bush administration official Ben Sasse (R) -- have all spent between $440,000 and $550,000 on television. Most late outside spending is benefitting Sasse.

-- Iowa: A month before the primary, the race for the Republican Senate nomination is between businessman Mark Jacobs and state Sen. Joni Ernst. Jacobs is outspending Ernst on TV, but high-profile endorsements and creative ads have helped Ernst stay competitive. Jacobs and Ernst have begun attacking each other, and outside groups are poised to get involved too. (Des Moines Register) Sen. Marco Rubio (R-Fla.) said Monday he'll back Ernst. (Des Moines Register)

-- Oregon: The FBI has begun conducting interviews as part of an investigation into Cover Oregon, the health care exchange botched so badly that officials opted to transition to the federal exchange. (Wall Street Journal) Reid's Take: Gov. John Kitzhaber (D) could feel the sting of Cover Oregon's failure, if Republicans had any kind of bench there. No Republican has won an Oregon governor's race since 1982.

-- Illinois: The House ethics committee said Monday it would continue to review payments Rep. Luis Gutierrez (D) made to a former staffer and Illinois lobbyist. That former staffer, Doug Scofield, was paid $590,000 as a contractor; House rules only allow contractors to perform staff duties, not legislative functions. The outside Office of Congressional Ethics said in a unanimous vote last year that relationship may have violated House rules and federal law. (Chicago Tribune)

-- Pennsylvania: Hillary Clinton will be the main draw at a May 15 fundraiser for former Rep. Marjorie Margolies (D), Chelsea Clinton's mother-in-law, in New York City. It's Clinton's first political event this year. Margolies is locked in a tough primary against three other Democrats vying for Rep. Allyson Schwartz's seat in the Philadelphia suburbs. (Politico) Good timing: News of the Clinton event comes two days after the New York Times wondered whether Hillary viewed Margolies as a potential albatross.

DC Digest: What's on tap today in DC.

-- President Obama sits down with meteorologists from New York, San Francisco, Seattle, Chicago and Columbia, S.C., to promote the climate change report coming out this morning. The interviews are embargoed until 5 p.m. Eastern Time. Obama and Vice President Biden meet Secretary of State John Kerry in the Oval Office later this afternoon. Biden will headline an opening ceremony for Asian American and Pacific Islander Heritage Month at the Interior Department, then he swears in Assistant Secretary of State Puneet Talwar this afternoon.

-- The House meets at noon, with first votes postponed until 6:30 p.m. The House will consider seven proposed measures under suspension, none of which are controversial.

-- The Senate meets at 10 a.m., with a vote to invoke cloture on a motion to proceed on the Shaheen-Portman bill, formally known as the Energy Savings and Industrial Competitiveness Act, at 11 a.m. Also, it's class photo day! The official photograph of the 113th Congress will take place at 2:15 p.m.

-- Harvard Law School Professor David Barron is the latest judicial nominee to run into trouble after the ACLU wrote a letter urging senators to put off a vote until the White House released memos Barron wrote as a Justice Department lawyer justifying the U.S. killing an American citizen overseas with a drone. Sen. Rand Paul (R-Ky.) will block Barron's nomination, and Sens. Mark Begich (D-Alaska) and Mary Landrieu (D-La.) are wavering. Sen. Mark Udall (D-Colo.), one of the leading skeptics of the drone program, is a no, and Sen. Ron Wyden (D-Ore.) won't commit to vote for Barron. (New York Times)

-- 63 members of Congress are spending a combined $38,000 a month on auto leases from their Congressional budgets. Rep. Randy Neugebauer (R-Texas) is spending the most, $1,318 per month, according to disclosure statements, while Reps. Emanuel Cleaver (D-Mo.), G.K. Butterfield (D-N.C.) and Gregory Meeks (D-N.Y.) are spending almost $1,000 a month to lease cars. (Atlanta Journal-Constitution)

TV Time Out: Our exclusive look at who's advertising, and where

-- Georgia: Somebody doesn't like Rep. Jack Kingston (R). Citizens for a Working America, a super PAC that helped knock off then-Rep. John Spratt (D-S.C.) in 2010 and ran an ad for Mitt Romney before the 2012 Iowa caucuses, is spending $500,000 on late ads opposing Kingston's Senate bid, according to an FEC report filed Friday. That's about a third of the total amount Kingston has spent on his own race.

-- Alaska: Watch out, Dan Sullivan (R). Put Alaska First, a Democratic super PAC funded largely by Senate Majority PAC, will spend $346,000 on ads targeting the establishment-favored Republican candidate, according to a report filed with the FEC. The group has already spent more than $1.3 million on behalf of Sen. Mark Begich (D), making Alaska one of the few states where Democrats have outspent Republicans.

-- Arkansas: Sen. Mark Pryor (D) continues his ad-buying spree, snapping up $215,000 in cable and broadcast buys running now through May 15. At the same time, the Government Integrity Fund Action Network, the conservative outside group, is up with $100,000 in new ads this week, bringing that group's total spending to more than $500,000.

-- Minnesota: Sen. Al Franken (D) is up with his first ad focusing on job training programs he's backed. He'll spent at least $40,000 running the ad on two Twin Cities stations. (Minneapolis Star-Tribune)

The Buried Lede: The nuggets that deserve the spotlight.

-- The backstory on Obama's interviews with meteorologists today, from Post reporter Juliet Eilperin's notebook: Meteorologists are one of the most targeted demographics for climate change advocates. That's because Americans trust them more than just about any other source of information, according to polling conducted by Yale and George Mason University.

-- Climate Central, a research group, provides detailed TV-ready graphics to 130 weather forecasters at 92 stations in 70 markets around the country. Obama's focus on the local anchors is a favorite White House trick for rolling out a new policy initiative.

B1: Business, politics and the business of politics

-- House Republicans' efforts to recruit and promote more women candidates have produced mixed results, and fewer women are running overall this year than in 2012. Of the 196 women running for House seats, 68 are Republicans; six have already won their primaries, including Utah's Mia Love and Virginia's Barbara Comstock. But nine have lost, including two promising candidates in Florida. Reps. Ann Wagner (R-Mo.) and Diane Black (R-Tenn.) are spearheading the GOP effort. (St. Louis Post-Dispatch)

-- Markets are up a hair after minimal gains yesterday. Asian and European markets traded only slightly lower today. (CNN)

C1: The long reads you'll need to check out before tonight's cocktail party.

-- A new study of Supreme Court voting habits finds justices are more likely to vote to uphold a petitoner's free speech rights when the justice agrees with the speech being exercised. Clarence Thomas and Antonin Scalia vote to uphold conservative speakers' rights much more often than those of liberal speakers; Ruth Bader Ginsburg and David Souter are more likely to vote to uphold the rights of liberal speakers. (New York Times)

C4: The comics page, fun things to read when you're bored at work

-- Blazing Saddles was released 40 years ago, and Mel Brooks is furious the American Film Institute only put it at sixth-best comedy of all time. USA Today's Bryan Alexander sits down with Brooks to talk about the film in today's paper.

-- "Unfortunately, there is one thin g standing between me and that property: The rightful owners." -- Hedley Lamarr

Attn Matt Drudge: Things conservatives will get outraged by today.

-- Way Too Early producer Louis Burgdorf celebrated Cinco de Mayo in style, with a sombrero on his head, a maraca in hand and a bottle of tequila on his lips. Newsbusters asks, not unreasonably: What if Fox News had pulled that stunt? (Newsbusters)

Attn HuffPo: What outrages liberals today

-- Tennessee state Sen. Stacey Campfield (R) said Monday on his Facebook page that Democrats bragging about the number of people who signed up to receive health care "is like Germans bragging about the number of manditory [sic] sign ups for 'train rides' for Jews in the 40s." Yikes. Even state Republican Party chairman Chris Devaney rebuked Campfield, calling the comments "ignorant and repugnant." (Washington Post, Huffington Post)