Republicans have a fight on their hands: 'Trump is losing and the Senate is leaning towards Democrats'
Donald Trump and Mitch McConnell (Screen Capture)

Senate Majority Leader Mitch McConnell breathed a sigh of relief after controversial former Kansas secretary of state Kris Kobach lost his state's Republican primary for the U.S. Senate.

The McConnell-aligned Senate Leadership Fund had invested $2.1 million to boost Rep. Roger Marshall, who won the primary and will face off against Democratic state Sen. Barbara Bollier, but the majority leader's intervention shows the challenge he faces in holding onto his own job, reported NPR.

"Right now Trump is losing and the Senate is leaning towards Democrats," said one GOP strategist.

The GOP currently holds a 53-47 majority in the Senate, but Republicans face a tough map for maintaining that control.

"Of the 10 most competitive Senate races, Republicans have only one likely prospect for a pickup in Alabama," NPR reported. "The remaining nine seats are GOP-held, and the party's candidates are down or tied in the polls across the board."

Republican strategists are most worried about Arizona, Colorado and North Carolina, but President Donald Trump's poor approval ratings put two states he won -- Iowa and Montana -- into play for Democrats.

"The dynamics that could cause him to win reelection may be out of his hands," said another Republican strategist. "He's now at the mercy of outside factors."

Even once reliably conservative Georgia carries a risk for Republicans, who have two incumbents fighting to hold onto their seats.

Sen. Kelly Loeffler is trying to keep her seat in a special election after her appointment to finish a term, and Sen. David Perdue is seeking a second term.