After nearly five months and more than 100 primaries and caucuses, the 2024 presidential nominating season comes to a close this month.

Voters in Montana, New Jersey, New Mexico, South Dakota and Washington, D.C., head to the polls Tuesday for both presidential and state primaries. Voters in Iowa, which already held its presidential caucuses, will cast ballots in state primaries.

The White House nominating calendar will wrap up four days later, with Democratic caucuses in Guam and the U.S. Virgin Islands on June 8.

And while President Biden and former President Trump clinched the Democratic and Republican nominations nearly three months ago, there's still some drama in the final contests.

WITH THE VERDICT IN AND HIS CRIMINAL TRIAL OVER, TRUMP IS ‘UNLEASHED’

Tuesday's Republicans primaries are the first since Trump was found guilty in his criminal trial in New York City, making history as the first former or current president to be convicted of felony crimes.

It's also the first round of GOP presidential contests since Trump's final rival for the nomination – former U.N. ambassador and former South Carolina Gov. Nikki Haley – said she would vote for Trump in the general election, after staying silent for months.

AFTER MONTHS OF SILENCE, WHAT NIKKI HALEY SAID ABOUT TRUMP

Haley, who suspended her campaign in early March, has continued to grab up to 20% of the vote in Republican presidential primaries even though she's essentially a zombie candidate. Haley will appear on the primary ballot in New Mexico.

The president will likely continue to face a protest vote through the "uncommitted" option on the ballot, as part of protests against his support for Israel in its war with Hamas in Gaza.

Tuesday's primaries set up battle for Senate majority

Three states are holding Senate primaries that will set up general election showdowns that may decide whether the Republicans win back control of the chamber.

In reliably red Montana, Tim Sheehy is the clear favorite to win the GOP Senate nomination and challenge Democratic Sen. Jon Tester in November.

Tester, whom the GOP considers extremely vulnerable in a state Trump won by 16-points four years ago, is being heavily targeted by Republicans.

Sheehy – a decorated military veteran and successful businessman who is backed by both Trump and the National Republican Senatorial Committee, which is the Senate GOP's campaign arm – is facing off against two rivals on Tuesday.

It's been 22 years since a Republican won a Senate election in New Mexico, a one-time swing state that nowadays leans blue. 

The last GOP politician to win was Sen. Pete Domenici, who was re-elected to a sixth term in 2002.

Fast-forward 22 years and now his daughter, businesswoman Nella Domenici, aims to end the losing streak.

The younger Domenici, who has years of experience in the finance industry, including serving as chief financial officer at Bridgewater Associates, will use her powerful political brand and ample name recognition in New Mexico as she challenges Democratic Sen. Martin Heinrich, who is running in November for a third six-year term.

Neither candidate faces a serious challenge in Tuesday's primaries.

SIX SENATE SEATS THE GOP AIMS TO FLIP IN NOVEMBER'S ELECTIONS

It's been over a half century since a Republican won a Senate election in blue state New Jersey.

But Republicans believe they have a shot this time around.

A major reason for the optimism is the prospect of a three-way race in New Jersey. Longtime Democratic Sen. Bob Menendez, who is on trial for federal corruption charges, is not running for re-election as a Democrat. On Monday, Menendez filed a petition with nearly 2,500 signatures to run for re-election as an independent. Polls indicate the embattled senator's independent bid would potentially take votes away from likely Democratic Senate nominee Rep. Andy Kim.

Kim, the frontrunner for the Democratic nomination, faces labor leader Patricia Campos-Medina and activist Lawrence Hamm in the primary.

The Republican primary will be a test of Trump's immense clout in contested GOP primaries.

Mendham Borough Mayor Christine Serrano Glassner was endorsed by Trump a couple of weeks ago at a large rally the former president held in Wildwood, New Jersey.

Real estate developer and hotelier Curtis Bashaw is the leading fundraiser in the Republican nomination race. 

He also enjoys an advantage on the primary ballot, as he has the county line in two-thirds of the state's 21 counties. 

New Jersey has long allowed counties to print ballots that include a prominent party line, which are widely viewed as helping candidates with establishment backing. Kim sued in federal court to overturn the county lines in the Democratic primary. But the GOP county lines were upheld.

Navy veteran Albert Harshaw and former Tabernacle Deputy Mayor Justin Murphy are also running in the Republican Senate primary.

Get the latest updates from the 2024 campaign trail, exclusive interviews and more at our Fox News Digital election hub.