Former U.S. President Donald Trump speaks during a rally in Cullman, Alabama, U.S., August 21, 2021.
Former U.S. President Donald Trump speaks during a rally in Cullman, Alabama, U.S., August 21, 2021. Reuters / MARVIN GENTRY

Donald Trump's sway with Republican voters faces a fresh test on Tuesday in Alabama, where Congressman Mo Brooks will try to win the Republican U.S. Senate nomination even after the former president switched his endorsement to Brooks' rival, Katie Britt.

In Virginia, Republican state Senator Jen Kiggans, a Navy veteran, was projected to have won a contest to face Elaine Luria, who along with Abigail Spanberger is one of the state's two vulnerable Democratic U.S. representatives up for re-election in the Nov. 8 midterms.

With Democratic President Joe Biden's approval ratings underwater, Republicans are favored to win control of the House of Representatives, where they need to flip only five Democratic seats for a majority, and could also take over the Senate.

A Republican-controlled House could stymie much of Biden's legislative agenda while launching politically damaging investigations into his administration.

In Alabama, Britt and Brooks are seeking to succeed retiring Republican Richard Shelby. Britt is Shelby's former chief of staff and led a statewide business group, while Brooks has served 12 years in the House.

The two advanced to a runoff contest after finishing ahead of a third candidate in May.

Trump initially backed Brooks, a staunch ally who has echoed his false claims that the 2020 presidential election was fraudulent. Brooks delivered a fiery speech to Trump supporters in Washington on Jan. 6, 2021, before some of them stormed the U.S. Capitol seeking to prevent the certification of Biden's victory.

But Trump rescinded his endorsement three months ago, after Brooks at a rally with the former president urged Republicans to put 2020 behind them.

Ten days before Tuesday's election, Trump endorsed Britt, who has led in recent polls.

Trump, who is weighing another White House run in 2024, has endorsed some 200 candidates in 2022, with mixed results in states including Georgia, Ohio and Pennsylvania.

Tuesday's winner will be heavily favored in November against the Democratic nominee, minister Will Boyd.

VIRGINIA RACES

In Virginia, Republicans' statewide success in 2021, headlined by Governor Glenn Youngkin's victory, has given them confidence they can flip two Democratic-held seats.

Luria, a former Navy officer, and Spanberger, a former CIA counter-terrorism officer, are seen as vulnerable in November given the national political environment favoring Republicans.

Luria is a member of the Jan. 6 House committee that has been holding a series of high-profile televised hearings aimed at examining Trump's role in the Capitol riot.

Kiggans, who has the support of Republican House leadership, won a four-way nominating contest on Tuesday and will face Luria in November, Edison Research projected.

With around 40% of the estimated vote tallied, several Republicans were locked in a tight battle for the right to take on Spanberger, according to Edison, including state Senator Bryce Reeves, an Army veteran, and Yesli Vega, an auxiliary deputy sheriff endorsed by U.S. Senator Ted Cruz.

Trump did not endorse anyone in either race, though the candidates have sought to position themselves as his supporters.