Fox News politics editor Chris Stirewalt weighs in on what the primaries in South Carolina and Virginia tell us to expect in November.
Trump-backed candidate poised to upset Virginia primary

Incumbent Republican South Carolina Rep. Mark Sanford, a frequent Trump critic who the president lambasted earlier in the day as “nothing but trouble” and “very unhelpful,” was ousted in Tuesday night’s primary by state Rep. Katie Arrington.

On a key primary night with elections also held in Maine, Virginia, Nevada and North Dakota, the results in South Carolina were an unmistakably positive referendum on President Trump’s tenure.

Arrington’s shock win was also a dramatic rebuke of Sanford’s heated “Never Trump”-style rhetoric and scandal-pocked career. It signaled that the president’s base in the state remains solidly behind him ahead of November’s midterm elections, despite withering criticism from both inside and outside the Republican party.

State Rep. Katie Arrington, a relative political newcomer who secured Trump’s backing, repeatedly bashed Sanford for deriding the president and even ran advertisements featuring video clips of Sanford’s Trump criticisms.

Mark Sanford, a frequent Trump critic, went head-to-head in Tuesday’s South Carolina primary with Trump backer Katie Arrington, a relative political newcomer.

(Sanford state portrait, Arrington campaign photo)

Earlier Tuesday, as the ballots were being counted, Sanford acknowledged in an interview that his criticisms of Trump had hurt him in the primary.

“Well I think it has probably hurt me in this race,” he said. “But again, there are no free lunches in life. I think there are times I have had to oppose the president because of stands I have had for a long time.”

The coastal 1st Congressional District is Republican-leaning, but contains sizable liberal pockets such as Charleston County, which went for Hillary Clinton in 2016.

Sanford has warned that Trump’s steel and aluminum tariffs will be “disastrous,” called the president intolerant and untrustworthy, and even appeared to blame him for the shooting at a Republican congressional baseball practice last year.

“I would argue that the president has unleashed — it’s partially, again, not in any way totally — but partially to blame for demons that have been unleashed,” Sanford said, after gunfire from a disaffected progressive loner nearly took the life of Majority Whip Steve Scalise, R-La.

Mark Sanford has been very unhelpful to me in my campaign to MAGA. He is MIA and nothing but trouble. He is better off in Argentina. I fully endorse Katie Arrington for Congress in SC, a state I love. She is tough on crime and will continue our fight to lower taxes. VOTE Katie!

— Donald J. Trump (@realDonaldTrump) June 12, 2018

Even before Trump took office, Sanford said the billionaire businessman should “just shut up” and “quit responding” to anyone critical of him on a personal or professional level.

Sanford…