PHOENIX — U.S. Sen. Jeff Flake was on the receiving end of a critical tweet from President Donald Trump early Wednesday, calling the Arizona lawmaker “toxic” and encouraging a rival for his seat.

Great to see that Dr. Kelli Ward is running against Flake Jeff Flake, who is WEAK on borders, crime and a non-factor in Senate. He's toxic!

— Donald J. Trump (@realDonaldTrump) August 17, 2017

Trump also took another Republican senator, Lindsey Graham, of South Carolina, to task. Flake and Graham have been critical of the president’s statements about last weekend’s deadly violence at a white supremacist rally in Virginia.

In his initial response, the president did not denounce the Ku Klux Klan or neo-Nazis. Trump said there were “two sides to every story” and that the white nationalists and anti-discrimination marchers were each to blame for the bloody fighting that left dozens injured and one woman dead.

We can't accept excuses for white supremacy & acts of domestic terrorism. We must condemn. Period.

— Jeff Flake (@JeffFlake) August 15, 2017

Flake has often been a detractor of Trump since he announced his candidacy for president. He has written a book that said the Republican Party lost its way based on Trump’s successful campaign.

Observers have said Flake could be facing a challenge in keeping his seat. A political action group has reportedly formed to defeat him, and another influential group, Great America PAC, has jumped in to help Kelli Ward’s efforts to unseat Flake.

But Flake told KTAR News 92.3 FM’s Mac & Gaydos earlier this month he didn’t think he would lose the party’s support because he sometimes opposed Trump.

Ward is a former state senator from Lake Havasu City. She has said U.S. Sen. John McCain should step aside because he is fighting brain cancer.

McCain, who has also been a target of Trump disapproval, defended his colleague with a tweet of his own.

.@JeffFlake is a principled legislator & always does what's right for the people of #AZ. Our state needs his leadership now more than ever.

— John McCain (@SenJohnMcCain) August 17, 2017

Ward thanked Trump for his public boost.

Thank you @realDonaldTrump Working hard so you have a conservative from AZ to help #MAGA. Arizonans excited to see you again next week! https://t.co/DZzduT31FN

— Dr. Kelli Ward (@kelliwardaz) August 17, 2017

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