Northern Mariana Islands Senate

In the event of a vacancy that occurs less than two years before the end of the Senator's term, the Governor of the Northern Mariana Islands appoints the runner-up of the most recent election. Should that individual decline, the next highest vote getting, unsuccessful candidate become the prospective appointee. Should all the previous candidate's decline, the Governor would then choose an eligible citizen for consideration.^[2] In the event a vacancy occurs more than two years before the next scheduled election, a special election is held.^[3]

In the 24th Commonwealth Legislature, the majority caucus consists of four Republicans and three allied independent lawmakers. Karl King-Nabors became President of the Senate after Dennis C. Mendiola was elevated to lieutenant governor after the death of Arnold Palacios. Corina Magofna became Vice President in July 2025. Since the start of the 24th Commonwealth Legislature, Francisco Q. Cruz and Donald M. Manglona have served as legislative secretary and Floor Leader respectively. Ronnie M. Calvo is a member of the majority caucus.^[4][5] As of August 2025, eight of the nine senators make up the majority caucus as all Senators except Celina Babauta are either committee chairs or in a leadership position.^[6]

In the November 2007 elections, the three senators up for re-election were all re-elected to another four-year term in the 16th and 17th Senate. The Covenant Party, which lost control of the House, entered into coalition with the Democrats and a lone Independent over the Senate's leadership and voting agenda. The CNMI Senate was controlled in 2016 by a Republican majority under Senate President Francisco Borja.^[11]

• Northern Mariana Islands House of Representatives
• List of Northern Mariana Islands Governors