MORNING READ

Barack Obama's endorsement of a fellow Democrat in 2006 is coming back to haunt him, liberal bloggers write. House Democrats vulnerable this year should follow Rep. Dan Boren's (D-Okla.) decision not to endorse Obama, according to conservative bloggers. And Republicans in Congress, still facing an uphill battle in November's election, can rebuild their party brand by blaming Democrats for oil prices, following through on their new economic agenda and striking a deal on labor-friendly legislation, suggest pro-Republican bloggers.

Back when Sen. Joe Lieberman (I-Conn.) was a Democrat facing a tough primary challenge two years ago, he begged Obama to endorse him, which Obama did, according to a "top Lieberman official" who talks to TPM's Greg Sargent. Now Lieberman is undercutting Obama on national security and could work against an Obama administration as chairman of the Senate Committee on Homeland Security, writes kos.

Boren, who explained his decision to not back Obama by saying Illinois senator hasn't worked in a bipartisan fashion, has given John McCain a "devastating talking point" and put other Blue Dog Democrats on the hot seat, writes The Corner's Mark Hemingway. One of those centrist Democrats, Rep. Nick Lampson (D-Texas), should quit supporting Obama or risk losing his seat in a heavily Republican district, writes RedState's Erick Erickson.

Senate Republicans, who are losing the gas prices debate, should quit offering subsidies to oil companies and instead focus on Democrats' preference for imported Saudi oil over domestic drilling, writes The Next Right's Josh Kahn. And Republicans should test Democratic consistency on the Employee Free Choice Act by offering a deal that would make it easy for unions to organize but just as easy for employees to drop their membership, writes Jon Henke, also at The Next Right.

Maybe House Republicans already understand the need to try something new, as they plan to roll out a new economic agenda that calls for a flat tax, an earmark moratorium and a pledge to balance the budget without raising taxes, writes RedState's Rob Bluey.

FROM THE BLOGS:
Lieberman Official: We Begged Obama - G. Sargent, TPM Election
Obama's Worst Decision - kos, Daily Kos
Obama: Too Liberal Even For Dems - Mark Hemingway, The Corner
Compare And Contrast Dems in Red Districts - E. Erickson, RedState
Obama Shows His Punch - Robert Borosage, Huffington Post
John McCain And Reproductive Rights - DemFromCT, Daily Kos
RNC, Let's Go Down That Road - Josh Orton, MyDD
Barr's Conscience Wrestles w/ Drug War - Michael Idov, The Plank
Get Carter - Christopher Orr, The Plank
McCain On Corporate Pay - Ramesh Ponnuru, The Corner
Voinovich Ripe For A Challenge - Jonathan Singer, MyDD
Offering Dems A Deal On Card Check - Jon Henke, The Next Right
House GOP's Bold Economic Agenda - Rob Bluey, RedState
How Did GOP Get Stuck Defending 'Big Oil'? - J. Kahn, The Next Right

OTHER NEWS SOURCES:
Republicans Gird For Big Losses In Congress - Wall Street Journal
Two New-Style Candidates Hit Old Notes On Economy - NYT
Bush Regrets Legacy As Man Of War - The Times
Insiders On Speed Dial - The Hill