WASHINGTON — As Mitch McConnell readies for a 2020 re-election campaign, his unwavering support for Donald Trump’s southern border wall gives the senator an important boost from the Republican Party’s conservative wing – activists who have not always been on his side.

Rep. James Comer, R-Ky., a McConnell ally, said he had heard “more compliments” about the Senate majority leader this week than ever before from members of the conservative House Freedom Caucus.

Last month the caucus pressured Trump to reject a Senate spending bill aimed at averting the shutdown because it didn’t include money for the wall Trump promised as a presidential candidate.

“Conservatives want Trump to have a win on the wall and Mitch McConnell is standing firm with Trump, even though they know probably deep down, ideologically, he would like to compromise and end the shutdown,” Comer said.

McConnell has said consistently for weeks that he won’t entertain any legislation that doesn’t include wall funding. Conservatives “appreciate he’s standing with the president,” Comer said.

McConnell made it clear last month that he didn’t want a shutdown, telling reporters there was “no education in the second kick of a mule.”

But he’s the leader of a caucus with 22 Republicans up for re-election in 2020, including 20 from states that Trump won. None of them want to give an inch to a potential primary challenge.

McConnell himself is up for re-election in a state where Trump is more popular than the six-term senator.

By resisting Democratic pressure to hold a vote on House spending bills to re-open the government, McConnell is now protecting his caucus members from casting votes that would put them at odds with Trump, said Sen. Roy Blunt, R-Mo., the policy chairman in charge of helping shape Senate Republicans’ legislative agenda.

“The majority leader is doing exactly what he should be doing,” Blunt said. “There’s no reason for us to have a lot of debates that don’t lead to any conclusion or take a lot of votes that only create bad feelings if they’re not going to create a result.”

Blunt said to ask senators to take votes that put them “in a position where they’re needlessly in conflict with the president in a way that produces no result is not what the members expect the leader to do.

“The leader is right and I don’t sense he feels any pressure to move from the position he’s in,” Blunt said.

Still, there is some pressure. Republicans facing challenging 2020 re-elections in states that Trump lost, including Sens. Cory Gardner of Colorado and Susan Collins of Maine, have called for the government to reopen even without an agreement on the border wall.

Others want the chamber to take a more active role, worried about a perception that the Senate is inert while furloughed federal workers go without paychecks and the Democratic-led House keeps passing legislation that would open parts of the government.

Sen. Ron Johnson, R-Wis., said he supports McConnell’s position, noting that among Republicans “There’s a lot of support to build the wall.”

At the same time, Johnson would like to demonstrate that the Senate is working to improve the situation for affected workers. He and Collins are pushing legislation to pay the roughly 420,000 federal employees who have been forced to work without pay.