U.S. Senator Ben Sasse (R-NE) joined a small group of Senators, led by Senator Jeff Flake (R-AZ), urging President Donald Trump veto any bill containing congressional earmarks. The letter was also signed by U.S. Sens. Mike Lee (R-UT), John McCain (R-AZ), Ted Cruz (R-TX), and Rand Paul (R-KY).
“This is pretty simple: earmarks promote a corrupt, pay-to-play politics and that’s part of the swamp that the President promised to drain,” said Sasse. “We’re respectfully asking the President to keep that promise and veto any bills that contain earmarks. This won’t be popular with the permanent-incumbency class but that’s exactly why it’s the right thing to do for America’s taxpayers.”

In 2011, Congress banned the practice of earmarking in which a single member of Congress could direct millions of federal dollars to their districts.  

View a signed copy of the letter here. Text of the letter can be viewed below.

Dear President Trump,
With our national debt set to top $20 trillion within days and growing at a rate of over half-a-trillion dollars a year, bringing fiscal sanity to the federal budget requires immediate attention and action.  We write today to urge opposition to any efforts by Congress to return to earmarking.
While cutting unnecessary and wasteful spending may be commonsense to most taxpayers, behind every dollar spent is a boisterous special interest group with the loudest being Congress itself.  Even with a full agenda that includes repealing Obamacare, reforming the tax code, easing the regulatory burden and strengthening our nation’s security, some lawmakers are focused on reviving the corrupt practice of earmarking that was ended in 2011 after what seemed like an endless series of corruption scandals.
Fondly described as a “favor factory” by a lobbyist convicted of exchanging gifts for government grants, earmarks represent the pay-to-play culture you have pledged to end.  It is unfathomable to those of us who fought to end earmarks and witnessed our colleagues go to jail for corruption that pork barrel politics would return, especially at this time when Americans are clearly fed up with business-as-usual. However, despite the success of the current moratorium enacted in both chamber of Congress, there are efforts underway seeking to revive the disdainful practice. 
President Reagan vetoed a highway bill in 1987 because it was larded up with 152 earmarks.  Escalating exponentially, the over-budget transportation bill signed into law in 2005 contained more 6,300 earmarks.  Earmark proponents are trying to reassure that this time will be different, promising fewer projects and even rebranding them as “congressionally-directed spending.”  With the serious fiscal problems facing our nation, processing thousands or even hundreds of pork requests will only distract and delay addressing pressing national needs and push spending decisions once again into the murky shadows.
We respectfully urge you to make it clear that you will veto any bill Congress sends to you containing earmarks within the legislative text or the accompanying report.  We look forward to working with you to make Washington more accountable and stop wasteful spending where it starts, which is often right here in Congress.