In a campaign email sent to supporters recently, Donald Trump Jr. called Sen. John Cornyn, R-Texas, President Donald Trump’s “biggest ally.”

He’s sort of correct. Cornyn does vote with President Donald Trump almost all of the time.

But Trump faces impeachment, and he had a 45 percent approval rating in Texas in a September Quinnipiac poll. The last incumbent Republican to run for the Senate in Texas, Ted Cruz, won by 2.6 percentage points in 2018.

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The email, sent by the Cornyn campaign on behalf of Trump Jr., said “My father, President Donald Trump, is taking a stand on our southern border, on lowering taxes for the middle-class, and on putting America first on the global stage. Despite his efforts, Democrats and out-of-state, Hollywood donors are trying to put a Texas-sized dent into my father’s efforts by taking down his biggest ally, Senator John Cornyn.”

The next day, the Cornyn campaign sent an almost identical email to donors from Trump Jr., but called Conryn “one of [Trump’s] biggest allies,” rather than “his biggest ally.”

According to a database compiled by FiveThirtyEight, a political statistical analysis site, Cornyn has voted in line with Trump’s position 95.4 percent of the time since Trump became president.

Among all current members of the Senate, Cornyn votes in line with Trump the fourth most often, behind only Kevin Cramer, R-North Dakota, Shelly Moore Capito, R-West Virginia and Martha McSally, R-Arizona.

Cornyn’s campaign did not respond to requests for comment.

According to the same database, Cornyn votes in line with Trump more often than Republican senators Cruz, Lindsey Graham of South Carolina, David Perdue of Georgia and Chuck Grassley of Iowa. All are outspoken about their support for the president and his policies.

Sean Theriault, a professor in the Department of Government at the University of Texas at Austin, said that aligning himself with the president is more likely to help Cornyn than hurt him.

“He’s trying to wrap himself in the flag of Donald Trump,” he said.

And, Theriault said, because Cornyn is running for re-election during a presidential election year, he’ll have an easier job winning support and enthusiasm alongside Trump’s campaign.

“[The party that] wins the state at the presidential level is likely to win the Senate race,” Theriault added.

The Texas Democratic Party pounced on Cornyn’s campaign email soon after it was sent, agreeing with Trump Jr.’s claim and encouraging residents to vote against Trump’s “enabler.”

“For once, Donald Jr is telling the absolute truth: There hasn’t been a bigger ally to Donald Trump than Texas’ gutless and weak Senator, John Cornyn. From supporting Trump’s useless border wall, to defending and echoing Trump’s vile rhetoric on communities of color, to standing with Trump and refusing to stand against the NRA, there simply hasn’t been a bigger enabler to Trump than John Cornyn,” the party’s communications director, Abhi Rahman, said in a statement.

There are seven Democrats who have already announced their campaigns for Cornyn’s Senate seat. They include M.J. Hegar, an Air Force veteran, Texas state senator Royce West, former U.S. Rep. Chris Bell, and Sema Hernandez, who ran against Beto O’Rourke last year in the Democratic primary for another Texas Senate seat.