Former President Trump has been endorsed by 37 House Republicans — including more than a third of the GOP members on Judiciary and Oversight, two committees he's pushing to investigate President Biden and Manhattan's district attorney.

Why it matters: Trump's endorsements, which also include five Republican senators, reflect the congressional wall of support he has built to boost his 2024 presidential campaign — and help him dig up dirt on his political and legal foes.

• Trump, now facing criminal charges in New York, frequently chats by phone with supporters such as House Judiciary chair Jim Jordan (R-Ohio) and GOP Conference chair Elise Stefanik (R-N.Y.) to discuss Republicans' probes into Biden and Manhattan DA Alvin Bragg.
• Jordan and Stefanik — also members of the Judiciary's panel that targets what it calls the “weaponization” of law enforcement against conservatives — are particularly key players in Trump's orbit.
• They wield significant influence on panels that have tried—so far unsuccessfully—to get documents and testimony from Bragg's probe into alleged hush money payments Trump made to porn star Stormy Daniels.

The big picture: Trump has been able to maintain a grip on much of the GOP base even as he's faced criminal investigations in New York and Georgia, and by the Justice Department.

• 9 of the 25 Republicans on the House Judiciary Committee support him.
• 11 of the 26 Republicans on House Oversight do as well.

Zoom in: Trump backers in the House leadership also include GOP Conference Secretary Rep. Richard Hudson (R-N.C.).

• Other notable House Republicans endorsing Trump include Jim Banks (Indiana), who is running for Senate, Small Business Committee chair Roger Williams (Texas), Veterans Affairs chair Mike Bost (Illinois), and Ronny Jackson (Texas).

• Trump's endorsements in the Senate: Lindsey Graham (R-S.C.), Tommy Tuberville (R-Ala.), J.D. Vance (R-Ohio), Eric Schmitt (R-Mo.), and Markwayne Mullin (R-Oka.).

Between the lines: In recent weeks, Jackson and Stefanik have been calling House colleagues on Trump's behalf, asking for endorsements, people familiar with the calls tell Axios.

• Team Trump has been keeping close tabs on who has endorsed — and who hasn't.
• At his rally in Waco, Texas, last weekend, Trump suggested that GOP lawmakers who did not endorse him were not welcome at his rallies: “If they don't endorse me, I said don't even come.”
• But Trump recognizes there are allies — such as Kentucky Rep. James Comer, chair of House Oversight — who have been helpful to him but have not yet endorsed.