McSally's concession comes more than a week after the Associated Press projected her Democratic challenger as the winner.
Dido's "White Flag" plays as the president and Republican Party senators are seen sinking together on the ill-fated "Jaws" ship.
"I'm not just running against Joe Biden," Trump said. "I'm running against the left-wing mob and the left-wing media, the big tech giants, and I'm also running against the RINOs."
Democrats need to gain at least four seats to take control of the Senate.
The Arizona senator was 2 points behind Democratic challenger Mark Kelly in one poll released Wednesday.
The Senate has 35 seats up for grabs in the 2020 election, with 23 of those now belonging to the GOP.
"I will keep fighting to break the gridlock and get more relief out to Arizona," Republican Senator Martha McSally told Arizona voters in a taxpayer-funded robocall as she trailed her Democratic challenger Mark Kelly in polls.
Nearly half of the registered voters polled said Sen. McSally has been "too supportive" of President Donald Trump.
At least eight GOP incumbents are in danger of losing their seats, while just one Democrat looks likely to be ousted.
Republican Senator McSally criticized what she termed a "radical political organisation" and called her Democratic rival "Counterfeit Kelly".
The Republican senator is engaged in a tight race in Arizona, which the latest opinion poll suggests is leaning toward the Democrats.
Democrats need to gain at least four seats to take control of the upper chamber of Congress from the GOP.
His lead over Martha McSally in the polls comes at a crucial moment for Trump's Supreme Court nomination as he could take office as soon as November 30.
Arizona Sen. Martha McSally was 8 points behind Democratic candidate Mark Kelly in the same week he had to apologize for a racist joke.
Democratic Senate candidate Mark Kelly also leads GOP Senator Martha McSally by a significant margin in the southwestern state.
"My brother's year in space was really hard on him and we tried to bring some light to his difficult ordeal, but this comment does not do that and I apologize and deeply regret it," Kelly said.
In order to take control of the Senate, Democrats would need to maintain all their current seats while gaining four more in the upcoming election.
Sen. Thom Tillis of North Carolina is 10 points behind Cal Cunningham with less than two months to go until election day.
Democrats would need to win at least four Republican seats while maintaining all their current seats to take control of the upper chamber of Congress.
Republican candidate for senate Martha McSally's primary against Daniel McCarthy is a battle she's expected to win Tuesday, but the results could foreshadow her losing the general election war in November.
The incumbent senator has consistently polled behind former astronaut Mark Kelly in the past few months.
Democrats hope to flip at least four seats while maintaining all their current seats in order to take control of the Senate.
Democratic Senate hopeful Mark Kelly said the president should consider retaliating against Russia via sanctions or other economic measures.
A new poll found Democrats are leading in the Arizona, North Carolina and Michigan Senate races as voters blame President Trump for the rise in coronavirus cases.
Senator Martha McSally said the recovery of the tourism and hospitality industries is "critical to our economic recovery."
The Arizona senator is down by double digits to her Democratic challenger, according to the survey.
Polls show Republican Senate candidate Martha McSally slipping in her race to beat well-funded former astronaut Democrat Mark Kelly in one of the most-watched races in the country—and conservative groups have begun to invest their money elsewhere.
The GOP incumbent is now down by double digits against her Democratic challenger.
The Democratic challenger is now ahead of the GOP senator by 7 points.
The Public Policy Polling poll found that Senators Susan Collins and Martha McSally have high disapproval ratings in their respective states.