As he does on many days, President Trump took to Twitter on Tuesday to attack the investigation into Russia’s interference in the 2016 presidential election — and to dismiss the probe altogether. He tweeted:

“The whole Russian Witch Hunt is a Fraud and a Hoax which should be ended immediately. Also, it was paid for by Crooked Hillary & DNC!”

But despite his incessant tweeting claiming his innocence, the president is losing the battle over the Russia narrative, including with his base.

The president, who is deeply mindful of Republicans (especially his base of supporters), has worked hard to discredit special counsel Robert S. Mueller III and his team. But recent polling shows that it is far less effective than he likely hopes.

As the number of investigations into Trump, his corporation, his foundation and his campaign mounts, the number of Republicans who believe Trump is being truthful is in the minority.

According to the most recent Washington Post poll, only 27 percent of Republicans believe Trump’s claim that Russia did not interfere in the 2016 presidential election. This is telling.

This data point was confirmed by another poll as well. More than 70 percent of Trump supporters say that the president has not been completely truthful on Russia, according to a recent CNN poll. This is after the president has spent more than a year calling the entire investigation a “witch hunt” motivated by the political bias of investigators.

To anyone who paid attention to the 2018 midterm election results, this is not that surprising. Despite Trump promising his supporters that there would be a “Red Wave” come November, it wasn’t even close. While rural voters came out heavily for Republicans, suburban voters turned against them, with many citing concerns about the president’s character, policies and questionable relationship with Russian leaders. The “Blue Wave” saw the Democrats taking the majority in the House, making significant gains at the state level and, in many cases, backing liberal policy ideas.

However, what may be surprising is how little the president seems to be aware of this pivot. Most presidents at this point have focused on winning over those people who have not supported them in the past. But Trump has been unable to keep his supporters, on the Russia issue at least, much less win new ones.

If this pattern continues, the president’s fate in 2020 could be much different from what he is expecting. With swing voters turning against him, Trump will have to depend on Republicans for a repeat victory. And their support for him could continue to decrease if the investigation into Russia’s interference in 2016 continues to cause them to lose confidence in the commander in chief.